0000950170-23-035096 | 10-Q | XBRL Viewer | Martin Marietta Materials INC

Supplemental Cash Flow Information (Tables)

6 Months Ended

Jun. 30, 2023

Supplemental Cash Flow Elements [Abstract]

Schedule of Noncash Investing and Financing Activities

Noncash investing and financing activities are as follows:


	Six Months Ended
	June 30,
	2023		2022
	(Dollars in Millions)
Accrued liabilities for purchases of property, plant and equipment	$	63.1	$	27.3
Remeasurement of operating lease right-of-use assets	$	1.4	$	(3.5	)
Remeasurement of finance lease right-of-use assets	$	—	$	(6.4	)
Right-of-use assets obtained in exchange for new operating lease liabilities	$	28.6	$	13.0
Right-of-use assets obtained in exchange for new finance lease liabilities	$	16.3	$	7.0
Acquisition of assets through asset exchange	$	5.2	$	—

Supplemental Disclosures of Cash Flow Information

Supplemental disclosures of cash flow information are as follows:


	Six Months Ended
	June 30,
	2023		2022
	(Dollars in Millions)
Cash paid for interest, net of capitalized amount	$	79.6	$	84.3
Cash paid for income taxes, net of refunds	$	83.0	$	42.9

Consolidated Balance Sheets (Unaudited) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022
Current Assets:
Cash and cash equivalents	$ 421.5	$ 358.0
Restricted cash	0.0	0.8
Restricted investments	702.3	704.6
Accounts receivable, net	979.2	785.9
Inventories, net	954.7	873.7
Current assets held for sale	44.8	73.2
Other current assets	89.8	80.7
Total Current Assets	3,192.3	2,876.9
Property, plant and equipment	10,859.3	10,661.0
Allowances for depreciation, depletion and amortization	(4,546.5)	(4,344.3)
Net property, plant and equipment	6,312.8	6,316.7
Goodwill	3,649.5	3,649.5
Other intangibles, net	833.8	847.8
Operating lease right-of-use assets, net	384.4	383.5
Noncurrent assets held for sale	325.6	372.5
Other noncurrent assets	547.8	546.7
Total Assets	15,246.2	14,993.6
Current Liabilities:
Accounts payable	346.9	385.0
Accrued salaries, benefits and payroll taxes	63.6	71.6
Accrued other taxes	90.7	55.4
Accrued interest	42.5	42.8
Current maturities of discharged long-term debt	700.0	699.1
Operating lease liabilities	53.2	52.1
Current liabilities held for sale	0.9	4.5
Other current liabilities	144.6	135.1
Total Current Liabilities	1,442.4	1,445.6
Long-term debt	4,343.1	4,340.9
Deferred income taxes, net	915.8	914.3
Noncurrent operating lease liabilities	337.0	335.9
Noncurrent liabilities held for sale	17.5	21.8
Other noncurrent liabilities	767.0	762.3
Total Liabilities	7,822.8	7,820.8
Equity:
Common stock, par value $0.01 per share (61.8 shares and 62.1 shares outstanding at June 30, 2023 and December 31, 2022, respectively)	0.6	0.6
Preferred stock, par value $0.01 per share	0.0	0.0
Additional paid-in capital	3,500.8	3,489.0
Accumulated other comprehensive loss	(35.7)	(38.5)
Retained earnings	3,955.4	3,719.4
Total Shareholders' Equity	7,421.1	7,170.5
Noncontrolling interests	2.3	2.3
Total Equity	7,423.4	7,172.8
Total Liabilities and Equity	$ 15,246.2	$ 14,993.6

Document and Entity Information - shares	6 Months Ended
Document and Entity Information - shares	Jun. 30, 2023	Jul. 24, 2023
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2023
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	Q2
Trading Symbol	MLM
Entity Registrant Name	MARTIN MARIETTA MATERIALS, INC.
Entity Central Index Key	0000916076
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Shell Company	false
Entity Small Business	false
Entity Emerging Growth Company	false
Title of 12(b) Security	Common Stock (Par Value $0.01)
Security Exchange Name	NYSE
Entity File Number	1-12744
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Incorporation, State or Country Code	NC
Entity Tax Identification Number	56-1848578
Entity Address, Address Line One	4123 Parklake Avenue
Entity Address, City or Town	Raleigh
Entity Address, State or Province	NC
Entity Address, Postal Zip Code	27612
City Area Code	919
Local Phone Number	781-4550
Document Quarterly Report	true
Document Transition Report	false
Entity Common Stock, Shares Outstanding		61,804,211

Revenues and Gross Profit - Additional Information (Detail 1)	Jun. 30, 2023	Jun. 30, 2022
Minimum \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2022-04-01
Revenue Recognition [Line Items]
Performance obligations, customer satisfaction period		1 month
Minimum \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2023-04-01
Revenue Recognition [Line Items]
Performance obligations, customer satisfaction period	1 month
Maximum \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2022-04-01
Revenue Recognition [Line Items]
Performance obligations, customer satisfaction period		23 months
Maximum \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2023-04-01
Revenue Recognition [Line Items]
Performance obligations, customer satisfaction period	28 months

Insider Trading Arrangements	3 Months Ended
Insider Trading Arrangements	Jun. 30, 2023
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false

Financial Instruments

6 Months Ended

Jun. 30, 2023

Financial Instruments Disclosure [Abstract]

Financial Instruments

The Company’s financial instruments include temporary cash investments, restricted cash, restricted investments, accounts receivable, note receivable, accounts payable, publicly-registered long-term notes and debentures.

Temporary cash investments are placed primarily in money market funds, money market demand deposit accounts and Eurodollar time deposit accounts with financial institutions. The Company’s cash equivalents have maturities of less than three months. Due to the short maturity of these investments, they are carried on the consolidated balance sheets at cost, which approximates fair value.

Restricted cash is held in a trust account with a third-party intermediary. Due to the short-term nature of this account, the carrying value of restricted cash approximates its fair value.

Restricted investments are held in a fund that invests solely in U.S. Treasury securities. The estimated fair value of the fund is valued at net asset value, which the fund seeks to maintain at one dollar per share. As such, the carrying value of the restricted investments approximates its fair value. The Company is restricted from accessing the investments, which will be used to settle the 2023 Notes and related interest payments. Investment returns on those trust assets are for the account of the Company if there are any remaining after satisfaction of all amounts payable in connection with the 2023 Notes.

Accounts receivable are due from a large number of customers, primarily in the construction industry, and are dispersed across wide geographic and economic regions. No single customer accounted for 10% or more of

consolidated accounts receivable at June 30, 2023 and December 31, 2022. The carrying values of accounts receivable approximate their fair values.

Note receivable is a promissory note with an unconsolidated affiliate (see Note 8) and is not publicly traded. Management estimates that the carrying value of the note receivable approximates its fair value.

Accounts payable represent amounts owed to suppliers and vendors. The estimated carrying value of accounts payable approximates its fair value due to the short-term nature of the payables.

The carrying value and fair value of the Company’s long-term debt were $5.04 billion and $4.41 billion, respectively, at June 30, 2023 and $5.04 billion and $4.36 billion, respectively, at December 31, 2022. The estimated fair value of the Company’s publicly-registered long-term debt was estimated based on Level 1 of the fair value hierarchy using quoted market prices.

Supplemental Cash Flow Information - Supplemental Disclosures of Cash Flow Information (Detail) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Supplemental Cash Flow Elements [Abstract]
Cash paid for interest, net of capitalized amount	$ 79.6	$ 84.3
Cash paid for income taxes, net of refunds	$ 83.0	$ 42.9

Significant Accounting Policies - Changes in Accumulated Other Comprehensive Loss Net of Tax (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance, Total Equity	$ 7,177.5	$ 6,431.0	$ 7,172.8	$ 6,537.6
Amounts reclassified from accumulated other comprehensive loss, net of tax	1.2	1.7	2.1	3.0
Other comprehensive earnings (loss), net of tax	1.7	1.2	2.8	(30.5)
Ending Balance, Total Equity	7,423.4	6,772.1	7,423.4	6,772.1
Pension and Postretirement Benefit Plans
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance, Total Equity	(35.5)	(129.7)	(36.5)	(97.6)
Other comprehensive earnings before reclassifications, net of tax		0.4	0.1	(33.0)
Amounts reclassified from accumulated other comprehensive loss, net of tax	1.2	1.7	2.1	3.0
Other comprehensive earnings (loss), net of tax	1.2	2.1	2.2	(30.0)
Ending Balance, Total Equity	(34.3)	(127.6)	(34.3)	(127.6)
Foreign Currency
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance, Total Equity	(1.9)	0.4	(2.0)
Other comprehensive earnings before reclassifications, net of tax	0.5	(0.9)	0.6	(0.5)
Other comprehensive earnings (loss), net of tax	0.5	(0.9)	0.6	(0.5)
Ending Balance, Total Equity	(1.4)	(0.5)	(1.4)	(0.5)
Accumulated Other Comprehensive Loss
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance, Total Equity	(37.4)	(129.3)	(38.5)	(97.6)
Other comprehensive earnings before reclassifications, net of tax	0.5	(0.5)	0.7	(33.5)
Amounts reclassified from accumulated other comprehensive loss, net of tax	1.2	1.7	2.1	3.0
Other comprehensive earnings (loss), net of tax	1.7	1.2	2.8	(30.5)
Ending Balance, Total Equity	$ (35.7)	$ (128.1)	$ (35.7)	$ (128.1)

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References + Details

- Definition

Amount of equity (deficit) attributable to parent and noncontrolling interest. Excludes temporary equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 24
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483421/250-10-45-24

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 23
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483421/250-10-45-23

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 5
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483421/250-10-45-5

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 5
-Subparagraph (c)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479654/326-10-65-5

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 20
-Name Accounting Standards Codification
-Section 65
-Paragraph 6
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480528/815-20-65-6

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 20
-Name Accounting Standards Codification
-Section 65
-Paragraph 6
-Subparagraph (h)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480528/815-20-65-6

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 20
-Name Accounting Standards Codification
-Section 65
-Paragraph 6
-Subparagraph (h)(1)(i)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480528/815-20-65-6

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 20
-Name Accounting Standards Codification
-Section 65
-Paragraph 6
-Subparagraph (h)(1)(iii)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480528/815-20-65-6

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 20
-Name Accounting Standards Codification
-Section 65
-Paragraph 6
-Subparagraph (h)(1)(iv)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480528/815-20-65-6

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 20
-Name Accounting Standards Codification
-Section 65
-Paragraph 6
-Subparagraph (i)(3)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480528/815-20-65-6

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 848
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 2
-Subparagraph (a)(3)(iii)(03)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483550/848-10-65-2

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 105
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 6
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479343/105-10-65-6

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 105
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 6
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479343/105-10-65-6

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 40
-Name Accounting Standards Codification
-Section 65
-Paragraph 2
-Subparagraph (f)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480016/944-40-65-2

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 40
-Name Accounting Standards Codification
-Section 65
-Paragraph 2
-Subparagraph (f)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480016/944-40-65-2

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 8
-Subparagraph (d)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482615/740-10-65-8

Reference 17: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 8
-Subparagraph (d)(3)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482615/740-10-65-8

Reference 18: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 4
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479654/326-10-65-4

Reference 19: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 15
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480336/718-10-65-15

Reference 20: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 15
-Subparagraph (f)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480336/718-10-65-15

Reference 21: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 15
-Subparagraph (f)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480336/718-10-65-15

Reference 22: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)(3)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483443/250-10-50-1

Reference 23: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 65
-Paragraph 1
-Subparagraph (e)(3)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480175/815-40-65-1

Reference 24: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 7
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483443/250-10-50-7

Reference 25: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482765/220-10-50-5

Reference 26: http://www.xbrl.org/2003/role/disclosureRef
-Topic 830
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481674/830-30-50-1

Reference 27: http://www.xbrl.org/2003/role/disclosureRef
-Topic 830
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481694/830-30-45-17

Reference 28: http://www.xbrl.org/2003/role/disclosureRef
-Topic 830
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 20
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481694/830-30-45-20

Reference 29: http://www.xbrl.org/2003/role/exampleRef
-Topic 946
-SubTopic 830
-Name Accounting Standards Codification
-Section 55
-Paragraph 11
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480167/946-830-55-11

Reference 30: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 205
-Name Accounting Standards Codification
-Section 45
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480767/946-205-45-3

Reference 31: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 505
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481004/946-505-50-3

Reference 32: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-04(19))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479617/946-210-S99-1

Reference 33: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.6-05(4))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479617/946-210-S99-2

Reference 34: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 3
-Subparagraph (SX 210.6-09(4)(b))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483575/946-220-S99-3

Reference 35: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 3
-Subparagraph (SX 210.6-09(6))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483575/946-220-S99-3

Reference 36: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 3
-Subparagraph (SX 210.6-09(7))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483575/946-220-S99-3

Reference 37: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480008/505-10-S99-1

Reference 38: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(g)(1)(ii))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

Reference 39: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 323
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481687/323-10-50-3

Reference 40: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 28
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482907/825-10-50-28

Reference 41: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
-Paragraph 15
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481231/810-10-45-15

Reference 42: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
-Paragraph 16
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481231/810-10-45-16

Reference 43: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 55
-Paragraph 4I
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481175/810-10-55-4I

+ Details

Consolidated Statements of Total Equity (Parenthetical) (Unaudited) - $ / shares	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Statement of Stockholders' Equity [Abstract]
Dividends declared	$ 0.66	$ 0.61	$ 1.32	$ 1.22

Commitments and Contingencies - Additional Information (Detail) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2023	Dec. 31, 2022
Commitments and Contingencies [Line Items]
Guarantee of affiliate's obligations	$ 15.0
Line of credit maturity period	2024-03
Other Receivable, after Allowance for Credit Loss, Related Party, Type [Extensible Enumeration]	Related Party [Member]
Other Receivable, after Allowance for Credit Loss, Related and Nonrelated Party Status [Extensible Enumeration]	Related Party [Member]
Outstanding letters of credit	$ 26.8
Interest-only loan receivable
Commitments and Contingencies [Line Items]
Maturity date	Dec. 31, 2024
Interest-only loan receivable \| Related Party [Member]
Commitments and Contingencies [Line Items]
Other Receivables	$ 6.0	$ 6.0

Inventories, Net - Schedule of Inventories Net (Detail) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022
Inventory Disclosure [Abstract]
Finished products	$ 1,060.9	$ 932.4
Products in process	21.0	24.8
Raw materials	87.3	71.7
Supplies and expendable parts	169.3	153.1
Total inventories	1,338.5	1,182.0
Less: allowances	(383.8)	(308.3)
Inventories, net	$ 954.7	$ 873.7

Revenues and Gross Profit (Tables)

6 Months Ended

Jun. 30, 2023

Revenues And Gross Profit [Abstract]

Summary of Information About the Company's Contract Balances

The following table presents information about the Company’s contract balances:


	June 30, 2023		December 31, 2022
	(Dollars in Millions)
Costs in excess of billings	$	22.3	$	5.1
Billings in excess of costs	$	6.9	$	10.5

Total Revenues and Gross Profit (Loss) by Product Line

The following table, which is reconciled to consolidated amounts, provides total revenues and gross profit (loss) by line of business: Building Materials (further divided by product line) and Magnesia Specialties. Interproduct revenues represent sales from the aggregates product line to the ready mixed concrete and asphalt and paving product lines and sales from the cement product line to the ready mixed concrete product line. Total revenues and gross profit (loss) reflect continuing operations only.


	Three Months Ended						Six Months Ended
	June 30,						June 30,
	2023			2022			2023			2022
	(Dollars in Millions)
Total revenues:
Building Materials business:
Aggregates	$	1,151.4		$	1,057.6		$	2,063.3		$	1,814.2
Cement		197.7			162.5			366.2			300.8
Ready mixed concrete		271.4			226.6			491.3			517.8
Asphalt and paving services		240.9			215.7			298.8			272.5
Less: interproduct revenues		(121.1	)		(102.4	)		(208.6	)		(191.5	)
Total Building Materials business		1,740.3			1,560.0			3,011.0			2,713.8
Magnesia Specialties		80.5			81.7			163.9			158.7
Total	$	1,820.8		$	1,641.7		$	3,174.9		$	2,872.5

Gross profit (loss):
Building Materials business:
Aggregates	$	370.9		$	307.3		$	608.9		$	410.0
Cement		93.3			50.7			140.4			77.5
Ready mixed concrete		35.4			14.6			46.6			36.6
Asphalt and paving services		36.5			26.5			16.0			13.4
Total Building Materials business		536.1			399.1			811.9			537.5
Magnesia Specialties		27.7			24.5			52.7			50.2
Corporate		(3.4	)		1.6			(1.4	)		(6.4	)
Total	$	560.4		$	425.2		$	863.2		$	581.3

Significant Accounting Policies - Additional Information (Detail) $ in Millions	3 Months Ended	6 Months Ended		12 Months Ended
	Jun. 30, 2022 USD ($)	Jun. 30, 2023 USD ($) Plant Facility Segment State	Jun. 30, 2022 USD ($)	Dec. 31, 2022 USD ($)
Significant Accounting Policies [Line Items]
Number of quarries and yards \| Facility		350
Number of states in which entity operates \| State		28
Reportable business segments \| Segment		2
Restricted cash		$ 0.0		$ 0.8
Number of days restricted from utilizing cash				180 days
Restricted investments		702.3		$ 704.6
0.650% Senior Notes, Due 2023 (discharged)
Significant Accounting Policies [Line Items]
Debt instrument, face amount		$ 700.0		$ 700.0
Interest rate on notes		0.65%		0.65%
Maturity year		2023		2023
Pension and Postretirement Benefit Plans
Significant Accounting Policies [Line Items]
Other comprehensive loss, before reclassifications, net of tax	$ (0.4)	$ (0.1)	$ 33.0
California
Significant Accounting Policies [Line Items]
Number of cement plants \| Plant		1

Consolidated Statements of Total Equity (Unaudited) - USD ($) $ in Millions	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Loss	Retained Earnings	Total Shareholders' Equity	Noncontrolling Interests
Beginning Balance, Total Equity at Dec. 31, 2021	$ 6,537.6	$ 0.6	$ 3,470.4	$ (97.6)	$ 3,161.9	$ 6,535.3	$ 2.3
Beginning Balance (in shares) at Dec. 31, 2021		62,400,000
Consolidated net earnings (loss)	387.7				387.9	387.9	(0.2)
Other comprehensive earnings / loss, net of tax	(30.5)			(30.5)		(30.5)
Dividends declared	(76.7)				(76.7)	(76.7)
Issuances of common stock for stock award plans	4.6		4.6			4.6
Shares withheld for employees' income tax obligations	(25.1)		(25.1)			(25.1)
Repurchases of common stock	(50.0)				(50.0)	(50.0)
Stock-based compensation expense	24.5		24.5			24.5
Ending Balance, Total Equity at Jun. 30, 2022	6,772.1	$ 0.6	3,474.4	(128.1)	3,423.1	6,770.0	2.1
Ending Balance (in shares) at Jun. 30, 2022		62,400,000
Beginning Balance, Total Equity at Mar. 31, 2022	6,431.0	$ 0.6	3,462.6	(129.3)	3,094.9	6,428.8	2.2
Beginning Balance (in shares) at Mar. 31, 2022		62,400,000
Consolidated net earnings (loss)	366.4				366.5	366.5	(0.1)
Other comprehensive earnings / loss, net of tax	1.2			1.2		1.2
Dividends declared	(38.3)				(38.3)	(38.3)
Issuances of common stock for stock award plans	0.1		0.1			0.1
Shares withheld for employees' income tax obligations	(0.7)		(0.7)			(0.7)
Stock-based compensation expense	12.4		12.4			12.4
Ending Balance, Total Equity at Jun. 30, 2022	6,772.1	$ 0.6	3,474.4	(128.1)	3,423.1	6,770.0	2.1
Ending Balance (in shares) at Jun. 30, 2022		62,400,000
Beginning Balance, Total Equity at Dec. 31, 2022	$ 7,172.8	$ 0.6	3,489.0	(38.5)	3,719.4	7,170.5	2.3
Beginning Balance (in shares) at Dec. 31, 2022	62,100,000	62,100,000
Consolidated net earnings (loss)	$ 470.2				469.7	469.7	0.5
Other comprehensive earnings / loss, net of tax	2.8			2.8		2.8
Dividends declared	(82.5)				(82.5)	(82.5)
Issuances of common stock for stock award plans	2.0		2.0			2.0
Issuances of common stock for stock award plans (in shares)		100,000
Shares withheld for employees' income tax obligations	(17.9)		(17.9)			(17.9)
Repurchases of common stock, Shares		(400,000)
Repurchases of common stock	(151.2)				(151.2)	(151.2)
Stock-based compensation expense	27.7		27.7			27.7
Distributions to owners of noncontrolling interest	(0.5)						(0.5)
Ending Balance, Total Equity at Jun. 30, 2023	$ 7,423.4	$ 0.6	3,500.8	(35.7)	3,955.4	7,421.1	2.3
Ending Balance (in shares) at Jun. 30, 2023	61,800,000	61,800,000
Beginning Balance, Total Equity at Mar. 31, 2023	$ 7,177.5	$ 0.6	3,487.2	(37.4)	3,724.6	7,175.0	2.5
Beginning Balance (in shares) at Mar. 31, 2023		62,000,000
Consolidated net earnings (loss)	348.6				348.3	348.3	0.3
Other comprehensive earnings / loss, net of tax	1.7			1.7		1.7
Dividends declared	(41.3)				(41.3)	(41.3)
Issuances of common stock for stock award plans	0.7		0.7			0.7
Shares withheld for employees' income tax obligations	(1.1)		(1.1)			(1.1)
Repurchases of common stock, Shares		(200,000)
Repurchases of common stock	(76.2)				(76.2)	(76.2)
Stock-based compensation expense	14.0		14.0			14.0
Distributions to owners of noncontrolling interest	(0.5)						(0.5)
Ending Balance, Total Equity at Jun. 30, 2023	$ 7,423.4	$ 0.6	$ 3,500.8	$ (35.7)	$ 3,955.4	$ 7,421.1	$ 2.3
Ending Balance (in shares) at Jun. 30, 2023	61,800,000	61,800,000

Inventories, Net

6 Months Ended

Jun. 30, 2023

Inventory Disclosure [Abstract]

Inventories, Net


	June 30,			December 31,
	2023			2022
	(Dollars in Millions)
Finished products	$	1,060.9		$	932.4
Products in process		21.0			24.8
Raw materials		87.3			71.7
Supplies and expendable parts		169.3			153.1
Total inventories		1,338.5			1,182.0
Less: allowances		(383.8	)		(308.3	)
Inventories, net	$	954.7		$	873.7

Segments (Tables)

6 Months Ended

Jun. 30, 2023

Segment Reporting [Abstract]

Financial Data for Continuing Operation for Company's Reportable Business Segments

The following table displays selected financial data for the Company’s reportable segments. Total revenues, as presented on the consolidated statements of earnings and comprehensive earnings, reflect the elimination of intersegment revenues, which represent sales from one segment to another segment. Total revenues and earnings (loss) from operations reflect continuing operations only. In 2022, earnings from operations for the West Group included a nonrecurring gain on divested assets of $151.7 million.


	Three Months Ended						Six Months Ended
	June 30,						June 30,
	2023			2022			2023			2022
	(Dollars in Millions)
Total revenues:
East Group	$	735.1		$	674.5		$	1,264.7		$	1,093.3
West Group		1,005.2			885.5			1,746.3			1,620.5
Total Building Materials business		1,740.3			1,560.0			3,011.0			2,713.8
Magnesia Specialties		80.5			81.7			163.9			158.7
Total	$	1,820.8		$	1,641.7		$	3,174.9		$	2,872.5

Earnings (Loss) from operations:
East Group	$	227.5		$	210.6		$	336.4		$	238.5
West Group		239.6			274.5			334.3			317.6
Total Building Materials business		467.1			485.1			670.7			556.1
Magnesia Specialties		23.3			20.3			43.9			41.8
Corporate		(27.1	)		(26.8	)		(55.3	)		(59.5	)
Total	$	463.3		$	478.6		$	659.3		$	538.4

Financial Instruments - Additional Information (Detail) $ in Millions	6 Months Ended	12 Months Ended
	Jun. 30, 2023 USD ($) Customer	Dec. 31, 2022 USD ($) Customer
Debt Instrument [Line Items]
Long-term debt, carrying values	$ 5,043.1	$ 5,040.0
Long-term debt, fair values	$ 4,410.0	$ 4,360.0
Customer Concentration Risk \| Accounts Receivable
Debt Instrument [Line Items]
Number of customer accounted for 10% or more of consolidated accounts receivable \| Customer	0	0
Customer Concentration Risk \| Accounts Receivable \| Minimum
Debt Instrument [Line Items]
Percentage of concentration risk	10.00%	10.00%

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482900/835-30-50-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(f))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-04(a))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-3

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 5: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 69B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481568/470-20-55-69B

Reference 6: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 69C
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481568/470-20-55-69C

Reference 7: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 69E
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481568/470-20-55-69E

Reference 8: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 69F
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481568/470-20-55-69F

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 11: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1D
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1D

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1D
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1D

Reference 17: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1D
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1D

Reference 18: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1E
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1E

Reference 19: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1E
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1E

Reference 20: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1E
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1E

Reference 21: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1F
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1F

Reference 22: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1F
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1F

Reference 23: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1F
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1F

Reference 24: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1F
-Subparagraph (b)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1F

Reference 25: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1I
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1I

+ Details

- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

+ References + Details

Supplemental Cash Flow Information - Schedule of Noncash Investing and Financing Activities (Detail) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Supplemental Cash Flow Elements [Abstract]
Accrued liabilities for purchases of property, plant and equipment	$ 63.1	$ 27.3
Remeasurement of operating lease right-of-use assets	1.4	(3.5)
Remeasurement of finance lease right-of-use assets	0.0	(6.4)
Right-of-use assets obtained in exchange for new operating lease liabilities	28.6	13.0
Right-of-use assets obtained in exchange for new finance lease liabilities	16.3	7.0
Acquisition of assets through asset exchange	$ 5.2	$ 0.0

Income Taxes	6 Months Ended
Income Taxes	Jun. 30, 2023
Income Tax Disclosure [Abstract]
Income Taxes	6. Income Taxes The effective income tax rate reflects the effect of federal and state income taxes on earnings and the impact of differences in book and tax accounting arising primarily from the permanent tax benefits associated with the statutory depletion deduction for mineral reserves. The effective income tax rates for continuing operations were 20.9% and 22.6% for the six months ended June 30, 2023 and 2022, respectively. The higher 2022 effective income tax rate versus 2023 was driven by the impact of the divestiture of the Colorado and Central Texas ready mixed concrete businesses.

- Definition

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480990/946-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(h)(2))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//740/tableOfContent

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-14

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 21
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-21

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 270
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482526/740-270-50-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 17
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-17

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 6.I.5.Q1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479360/740-10-S99-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 11.C)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479360/740-10-S99-2

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482603/740-30-50-2

+ Details

Revenues and Gross Profit - Summary of Information About the Company's Contract Balances (Detail) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022
Revenue from Contract with Customer [Abstract]
Costs in excess of billings	$ 22.3	$ 5.1
Billings in excess of costs	$ 6.9	$ 10.5

Significant Accounting Policies (Tables)

6 Months Ended

Jun. 30, 2023

Significant Accounting Policies [Line Items]

Reconciliation of Cash, Cash Equivalents and Restricted Cash

The following table reconciles cash, cash equivalents and restricted cash as reported on the consolidated balance sheets to the aggregated amounts presented on the consolidated statements of cash flows:


	June 30,		December 31,
	2023		2022
	(Dollars in Millions)
Cash and cash equivalents	$	421.5	$	358.0
Restricted cash		—		0.8
Total cash, cash equivalents and restricted cash presented in the consolidated statements of cash flows	$	421.5	$	358.8

Consolidated Comprehensive Earnings (Loss)

Consolidated comprehensive earnings (loss) attributable to Martin Marietta is as follows:


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2023		2022		2023		2022
	(Dollars in Millions)
Net earnings attributable to Martin Marietta	$	348.3	$	366.5	$	469.7	$	387.9
Other comprehensive earnings (loss), net of tax		1.7		1.2		2.8		(30.5	)
Consolidated comprehensive earnings attributable to Martin Marietta	$	350.0	$	367.7	$	472.5	$	357.4

Changes in Accumulated Other Comprehensive Loss Net of Tax

The components of the changes in accumulated other comprehensive loss, net of tax, are as follows:


	(Dollars in Millions)
	Pension and Postretirement Benefit Plans			Foreign Currency			Accumulated Other Comprehensive Loss
	Three Months Ended June 30, 2023
Balance at beginning of period	$	(35.5	)	$	(1.9	)	$	(37.4	)
Other comprehensive earnings before reclassifications, net of tax		—			0.5			0.5
Amounts reclassified from accumulated other comprehensive loss, net of tax		1.2			—			1.2
Other comprehensive earnings, net of tax		1.2			0.5			1.7
Balance at end of period	$	(34.3	)	$	(1.4	)	$	(35.7	)

	Three Months Ended June 30, 2022
Balance at beginning of period	$	(129.7	)	$	0.4		$	(129.3	)
Other comprehensive earnings (loss) before reclassifications, net of tax		0.4			(0.9	)		(0.5	)
Amounts reclassified from accumulated other comprehensive loss, net of tax		1.7			—			1.7
Other comprehensive earnings (loss), net of tax		2.1			(0.9	)		1.2
Balance at end of period	$	(127.6	)	$	(0.5	)	$	(128.1	)


	(Dollars in Millions)
	Pension and Postretirement Benefit Plans			Foreign Currency			Accumulated Other Comprehensive Loss
	Six Months Ended June 30, 2023
Balance at beginning of period	$	(36.5	)	$	(2.0	)	$	(38.5	)
Other comprehensive earnings before reclassifications, net of tax		0.1			0.6			0.7
Amounts reclassified from accumulated other comprehensive loss, net of tax		2.1			—			2.1
Other comprehensive earnings, net of tax		2.2			0.6			2.8
Balance at end of period	$	(34.3	)	$	(1.4	)	$	(35.7	)

	Six Months Ended June 30, 2022
Balance at beginning of period	$	(97.6	)	$	—		$	(97.6	)
Other comprehensive loss before reclassifications, net of tax		(33.0	)		(0.5	)		(33.5	)
Amounts reclassified from accumulated other comprehensive loss, net of tax		3.0			—			3.0
Other comprehensive loss, net of tax		(30.0	)		(0.5	)		(30.5	)
Balance at end of period	$	(127.6	)	$	(0.5	)	$	(128.1	)

Noncurrent Deferred Tax Assets Recorded In Accumulated Other Comprehensive Loss

Changes in net noncurrent deferred tax assets related to accumulated other comprehensive loss are as follows:


	Pension and Postretirement Benefit Plans
	Three Months Ended						Six Months Ended
	June 30,						June 30,
	2023			2022			2023			2022
	(Dollars in Millions)
Balance at beginning of period	$	49.8		$	80.2		$	50.1		$	69.7
Tax effect of other comprehensive (earnings) loss		(0.4	)		(0.7	)		(0.7	)		9.8
Balance at end of period	$	49.4		$	79.5		$	49.4		$	79.5

Reclassification Out of Accumulated Other Comprehensive Loss

Reclassifications out of accumulated other comprehensive loss are as follows:


	Three Months Ended						Six Months Ended						Affected line items in the consolidated
	June 30,						June 30,						statements of earnings
	2023			2022			2023			2022			and comprehensive earnings
	(Dollars in Millions)
Pension and postretirement benefit plans
Amortization of:
Prior service cost	$	1.6		$	1.2		$	2.8		$	2.1
Actuarial loss		—			1.1			—			1.9
		1.6			2.3			2.8			4.0		Other nonoperating income, net
Tax effect		(0.4	)		(0.6	)		(0.7	)		(1.0	)	Income tax expense
Total	$	1.2		$	1.7		$	2.1		$	3.0

Basic and Diluted Earnings from Continuing Operations Per Common Share

The following table reconciles the denominator for basic and diluted earnings from continuing operations per common share:


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2023		2022		2023		2022
	(In Millions)
Basic weighted-average common shares outstanding		61.9		62.4		62.0		62.4
Effect of dilutive employee and director awards		0.2		0.1		0.2		0.2
Diluted weighted-average common shares outstanding		62.1		62.5		62.2		62.6

Pension and Postretirement Benefits - Schedule of Components of Net Periodic Benefit Cost (Credit) (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Pension
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 9.3	$ 14.0	$ 16.4	$ 24.0
Interest cost	14.6	11.9	25.7	20.6
Expected return on assets	(20.3)	(22.5)	(35.7)	(38.7)
Prior service cost (credit)	1.7	1.4	2.9	2.5
Actuarial loss (gain)	0.2	1.2	0.3	2.0
Net periodic benefit cost (credit)	5.5	6.0	9.6	10.4
Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	0.0	0.0	0.0	0.0
Interest cost	0.2	0.1	0.2	0.2
Expected return on assets	0.0	0.0	0.0	0.0
Prior service cost (credit)	(0.1)	(0.2)	(0.1)	(0.4)
Actuarial loss (gain)	(0.2)	(0.1)	(0.3)	(0.1)
Net periodic benefit cost (credit)	$ (0.1)	$ (0.2)	$ (0.2)	$ (0.3)

Consolidated Statements of Earnings and Comprehensive Earnings (Unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Total Revenues	$ 1,820.8	$ 1,641.7	$ 3,174.9	$ 2,872.5
Total Cost of Revenues	1,260.4	1,216.5	2,311.7	2,291.2
Gross Profit	560.4	425.2	863.2	581.3
Selling, general and administrative expenses	111.6	104.1	216.0	201.2
Acquisition and integration expenses	0.4	2.9	1.2	4.3
Other operating income, net	(14.9)	(160.4)	(13.3)	(162.6)
Earnings from Operations	463.3	478.6	659.3	538.4
Interest expense	42.2	43.1	84.3	83.6
Other nonoperating income, net	(18.7)	(22.0)	(34.9)	(32.9)
Earnings from continuing operations before income tax expense	439.8	457.5	609.9	487.7
Income tax expense	91.9	104.4	127.5	110.2
Earnings from continuing operations	347.9	353.1	482.4	377.5
Earnings (Loss) from discontinued operations, net of income tax expense (benefit)	0.7	13.3	(12.2)	10.2
Consolidated net earnings	348.6	366.4	470.2	387.7
Less: Net earnings (loss) attributable to noncontrolling interests	0.3	(0.1)	0.5	(0.2)
Net Earnings Attributable to Martin Marietta	348.3	366.5	469.7	387.9
Consolidated Comprehensive Earnings (Loss) :
Consolidated comprehensive earnings attributable to Martin Marietta	350.0	367.7	472.5	357.4
Earnings (Loss) attributable to noncontrolling interests	0.2	(0.1)	0.5	(0.2)
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	$ 350.2	$ 367.6	$ 473.0	$ 357.2
Net Earnings (Loss) Attributable to Martin Marietta Per Common Share:
Basic from continuing operations attributable to common shareholders	$ 5.61	$ 5.66	$ 7.78	$ 6.06
Basic from discontinued operations attributable to common shareholders	0.01	0.21	(0.2)	0.16
Basic attributable to common shareholders	5.62	5.87	7.58	6.22
Diluted from continuing operations attributable to common shareholders	5.60	5.65	7.76	6.04
Diluted from discontinued operations attributable to common shareholders	0.01	0.21	(0.20)	0.16
Diluted attributable to common shareholders	$ 5.61	$ 5.86	$ 7.56	$ 6.20
Weighted-Average Common Shares Outstanding:
Basic	61.9	62.4	62.0	62.4
Diluted	62.1	62.5	62.2	62.6

Pay vs Performance Disclosure - USD ($) $ in Millions	3 Months Ended		6 Months Ended
Pay vs Performance Disclosure - USD ($) $ in Millions	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Pay vs Performance Disclosure
Net Income (Loss)	$ 348.3	$ 366.5	$ 469.7	$ 387.9

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(g)(1)(ii))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 323
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481687/323-10-50-3

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 28
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482907/825-10-50-28

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482765/220-10-50-6

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483443/250-10-50-3

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483443/250-10-50-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 65
-Paragraph 1
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480175/815-40-65-1

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483443/250-10-50-8

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483443/250-10-50-9

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 11
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483443/250-10-50-11

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 11
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483443/250-10-50-11

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483443/250-10-50-4

Reference 13: http://www.xbrl.org/2003/role/exampleRef
-Topic 946
-SubTopic 830
-Name Accounting Standards Codification
-Section 55
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480167/946-830-55-10

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section 45
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483581/946-220-45-7

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(18))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483586/944-220-S99-1

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-22

Reference 17: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(9))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483575/946-220-S99-1

Reference 18: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 3
-Subparagraph (SX 210.6-09(1)(d))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483575/946-220-S99-3

Reference 19: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1A
-Subparagraph (SX 210.13-01(a)(4)(i))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480097/470-10-S99-1A

Reference 20: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1A
-Subparagraph (SX 210.13-01(a)(4)(ii))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480097/470-10-S99-1A

Reference 21: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1A
-Subparagraph (SX 210.13-01(a)(4)(iii)(A))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480097/470-10-S99-1A

Reference 22: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1A
-Subparagraph (SX 210.13-01(a)(4)(iv))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480097/470-10-S99-1A

Reference 23: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1A
-Subparagraph (SX 210.13-01(a)(5))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480097/470-10-S99-1A

Reference 24: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1B
-Subparagraph (SX 210.13-02(a)(4)(i))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480097/470-10-S99-1B

Reference 25: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1B
-Subparagraph (SX 210.13-02(a)(4)(iii)(A))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480097/470-10-S99-1B

Reference 26: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1B
-Subparagraph (SX 210.13-02(a)(4)(iii)(B))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480097/470-10-S99-1B

Reference 27: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1B
-Subparagraph (SX 210.13-02(a)(4)(iv))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480097/470-10-S99-1B

Reference 28: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1B
-Subparagraph (SX 210.13-02(a)(5))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480097/470-10-S99-1B

Reference 29: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 30
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-30

Reference 30: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-32

Reference 31: http://www.xbrl.org/2003/role/disclosureRef
-Topic 260
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 60B
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482689/260-10-45-60B

Reference 32: http://www.xbrl.org/2003/role/exampleRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 31
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-31

Reference 33: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-32

Reference 34: http://www.xbrl.org/2003/role/disclosureRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483499/205-20-50-7

Reference 35: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482740/230-10-45-28

Reference 36: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1A
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482790/220-10-45-1A

Reference 37: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1B
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482790/220-10-45-1B

Reference 38: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(20))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483621/220-10-S99-2

Reference 39: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(22))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483589/942-220-S99-1

+ Details

Significant Accounting Policies - Reclassifications Out of Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Tax benefit	$ 91.9	$ 104.4	$ 127.5	$ 110.2
Earnings from Continuing Operations	1.2	1.7	2.1	3.0
Pension and Postretirement Benefit Plans
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Earnings from Continuing Operations	1.2	1.7	2.1	3.0
Reclassification out of Accumulated Other Comprehensive Income \| Pension and Postretirement Benefit Plans
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Prior service cost	1.6	1.2	2.8	2.1
Actuarial loss	0.0	1.1	0.0	1.9
Tax benefit	(0.4)	(0.6)	(0.7)	(1.0)
Reclassification out of Accumulated Other Comprehensive Income \| Pension and Postretirement Benefit Plans \| Other Nonoperating Income, Net
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total reclassifications out of accumulated other comprehensive loss before taxes	$ 1.6	$ 2.3	$ 2.8	$ 4.0

- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References + Details

Significant Accounting Policies

6 Months Ended

Jun. 30, 2023

Accounting Policies [Abstract]

Significant Accounting Policies

Organization

Martin Marietta Materials, Inc. (the Company or Martin Marietta) is a natural resource-based building materials company. As of June 30, 2023, the Company supplies aggregates (crushed stone, sand and gravel) through its network of approximately 350 quarries, mines and distribution yards in 28 states, Canada and The Bahamas. Martin Marietta also provides cement and downstream products and services, namely, ready mixed concrete, asphalt and paving, in vertically-integrated structured markets where the Company also has a leading aggregates position. In addition, the Company has one cement plant that is classified as assets held for sale and reported as discontinued operations as of and for the six months ended June 30, 2023. The Company's Stockton, California cement import terminal, through the date of disposal (see Note 2), was reported as discontinued operations for the three and six months ended June 30, 2023 and 2022, and classified as assets held for sale as of December 31, 2022. The Company’s heavy-side building materials are used in infrastructure, nonresidential and residential construction projects. Aggregates are also used in agricultural, utility and environmental applications and as railroad ballast. The aggregates, cement, ready mixed concrete, asphalt and paving product lines are reported collectively as the “Building Materials” business.

The Company’s Building Materials business includes two reportable segments: the East Group and the West Group.


BUILDING MATERIALS BUSINESS (continuing operations only)
Reportable Segments	East Group	West Group
Operating Locations	Alabama, Florida, Georgia, Indiana, Iowa, Kansas, Kentucky, Maryland, Minnesota, Missouri, Nebraska, North Carolina, Ohio, Pennsylvania, South Carolina, Tennessee, Virginia, West Virginia, Nova Scotia and The Bahamas	Arizona, Arkansas, California, Colorado, Louisiana, Oklahoma, Texas, Utah, Washington and Wyoming

Product Lines	Aggregates and Asphalt	Aggregates, Cement, Ready Mixed Concrete, Asphalt and Paving

The Company’s Magnesia Specialties business, which represents a separate reportable segment, has manufacturing facilities in Manistee, Michigan, and Woodville, Ohio. The Magnesia Specialties business produces magnesia-based chemicals products used in industrial, agricultural and environmental applications, and dolomitic lime sold primarily to customers for steel production and soil stabilization.

Basis of Presentation and Use of Estimates

The accompanying unaudited consolidated financial statements of the Company have been prepared in accordance with accounting principles generally accepted in the United States (U.S. GAAP) for interim financial information and with the instructions to the Quarterly Report on Form 10-Q and in Article 10 of Regulation S-X. The Company has continued to follow the accounting policies set forth in the audited consolidated financial statements and related notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2022. In the opinion of management, the interim consolidated financial information provided herein reflects all adjustments, consisting of normal recurring accruals, necessary for a fair statement of the results of operations, financial position

and cash flows for the interim periods. The consolidated results of operations for the three and six months ended June 30, 2023 are not necessarily indicative of the results expected for other interim periods or the full year. The consolidated balance sheet at December 31, 2022 has been derived from the audited consolidated financial statements at that date but does not include all of the information and notes required by U.S. GAAP for complete financial statements. These consolidated financial statements should be read in conjunction with the audited consolidated financial statements and notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2022.

The preparation of the Company’s consolidated financial statements requires management to make certain estimates and assumptions about future events. As future events and their effects cannot be fully determined with precision, actual results could differ significantly from estimates. Changes in estimates are reflected in the consolidated financial statements in the period in which the change in estimate occurs.

Revenue Recognition

Total revenues include sales of products and services to customers, net of discounts or allowances, if any, and freight and delivery costs billed to customers. Product revenues are recognized when control of the promised good is transferred to unaffiliated customers, typically when finished products are shipped. Intersegment and interproduct revenues are eliminated in consolidation. Service revenues are derived from the paving business and are recognized using the percentage-of-completion method under the cost-to-cost approach. When the Company arranges third-party freight to deliver products to customers, the Company has elected the delivery to be a fulfillment activity rather than a separate performance obligation. Further, the Company acts as a principal in the delivery arrangements and, as required by Accounting Standards Codification (ASC) 606, the related revenues and costs are presented gross in the consolidated statements of earnings and are recognized consistently with the timing of the product revenues.

Restricted Cash

At December 31, 2022, the Company had restricted cash of $0.8 million, which was invested in an account designated for the purchase of like-kind exchange replacement assets under Section 1031 of the Internal Revenue Code and related IRS procedures (Section 1031). The Company was restricted from utilizing the cash for purposes other than the purchase of qualified assets for 180 days from receipt of the proceeds from the sale of the exchanged property. Any unused cash at the end of the 180 days was transferred to unrestricted accounts of the Company and used for general corporate purposes. There was no restricted cash at June 30, 2023.

The statements of cash flows reflect cash flow changes and balances for cash, cash equivalents and restricted cash on an aggregated basis. The following table reconciles cash, cash equivalents and restricted cash as reported on the consolidated balance sheets to the aggregated amounts presented on the consolidated statements of cash flows:


	June 30,		December 31,
	2023		2022
	(Dollars in Millions)
Cash and cash equivalents	$	421.5	$	358.0
Restricted cash		—		0.8
Total cash, cash equivalents and restricted cash presented in the consolidated statements of cash flows	$	421.5	$	358.8

Restricted Investments

At June 30, 2023 and December 31, 2022, the Company had $702.3 million and $704.6 million, respectively, of restricted investments, representing assets irrevocably transferred to an escrow trust account to satisfy and discharge the Company’s $700.0 million of 0.650% Senior Notes due 2023 (the 2023 Notes) (see Note 4). The assets in the escrow trust account could not be used for any purpose other than to satisfy the remaining interest payments and to repay the principal amount of the 2023 Notes on the maturity date of July 15, 2023. The assets transferred to the escrow trust account were invested in a U.S. Treasury securities fund (see Note 5) and investment returns on those trust assets were for the account of the Company (after satisfaction of all amounts payable in connection with the 2023 Notes). The Company consolidated the trust account on its balance sheets at June 30, 2023 and December 31, 2022.

Consolidated Comprehensive Earnings (Loss) and Accumulated Other Comprehensive Loss

Consolidated comprehensive earnings (loss) consist of consolidated net earnings, adjustments for the funded status of pension and postretirement benefit plans and foreign currency translation adjustments, and are presented in the Company’s consolidated statements of earnings and comprehensive earnings.

Consolidated comprehensive earnings (loss) attributable to Martin Marietta is as follows:


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2023		2022		2023		2022
	(Dollars in Millions)
Net earnings attributable to Martin Marietta	$	348.3	$	366.5	$	469.7	$	387.9
Other comprehensive earnings (loss), net of tax		1.7		1.2		2.8		(30.5	)
Consolidated comprehensive earnings attributable to Martin Marietta	$	350.0	$	367.7	$	472.5	$	357.4

Accumulated other comprehensive loss consists of unrecognized gains and losses related to the funded status of the pension and postretirement benefit plans and foreign currency translation and is presented on the Company’s consolidated balance sheets.

The components of the changes in accumulated other comprehensive loss, net of tax, are as follows:


	(Dollars in Millions)
	Pension and Postretirement Benefit Plans			Foreign Currency			Accumulated Other Comprehensive Loss
	Three Months Ended June 30, 2023
Balance at beginning of period	$	(35.5	)	$	(1.9	)	$	(37.4	)
Other comprehensive earnings before reclassifications, net of tax		—			0.5			0.5
Amounts reclassified from accumulated other comprehensive loss, net of tax		1.2			—			1.2
Other comprehensive earnings, net of tax		1.2			0.5			1.7
Balance at end of period	$	(34.3	)	$	(1.4	)	$	(35.7	)

	Three Months Ended June 30, 2022
Balance at beginning of period	$	(129.7	)	$	0.4		$	(129.3	)
Other comprehensive earnings (loss) before reclassifications, net of tax		0.4			(0.9	)		(0.5	)
Amounts reclassified from accumulated other comprehensive loss, net of tax		1.7			—			1.7
Other comprehensive earnings (loss), net of tax		2.1			(0.9	)		1.2
Balance at end of period	$	(127.6	)	$	(0.5	)	$	(128.1	)


	(Dollars in Millions)
	Pension and Postretirement Benefit Plans			Foreign Currency			Accumulated Other Comprehensive Loss
	Six Months Ended June 30, 2023
Balance at beginning of period	$	(36.5	)	$	(2.0	)	$	(38.5	)
Other comprehensive earnings before reclassifications, net of tax		0.1			0.6			0.7
Amounts reclassified from accumulated other comprehensive loss, net of tax		2.1			—			2.1
Other comprehensive earnings, net of tax		2.2			0.6			2.8
Balance at end of period	$	(34.3	)	$	(1.4	)	$	(35.7	)

	Six Months Ended June 30, 2022
Balance at beginning of period	$	(97.6	)	$	—		$	(97.6	)
Other comprehensive loss before reclassifications, net of tax		(33.0	)		(0.5	)		(33.5	)
Amounts reclassified from accumulated other comprehensive loss, net of tax		3.0			—			3.0
Other comprehensive loss, net of tax		(30.0	)		(0.5	)		(30.5	)
Balance at end of period	$	(127.6	)	$	(0.5	)	$	(128.1	)

The $33.0 million, net of tax, other comprehensive loss before reclassifications in the Pension and Postretirement Benefit Plans for the six months ended June 30, 2022 was driven by the remeasurement of the funded status of the Company’s qualified pension plan, required as a result of a plan amendment that provided an enhanced benefit for eligible hourly employees.

Changes in net noncurrent deferred tax assets related to accumulated other comprehensive loss are as follows:


	Pension and Postretirement Benefit Plans
	Three Months Ended						Six Months Ended
	June 30,						June 30,
	2023			2022			2023			2022
	(Dollars in Millions)
Balance at beginning of period	$	49.8		$	80.2		$	50.1		$	69.7
Tax effect of other comprehensive (earnings) loss		(0.4	)		(0.7	)		(0.7	)		9.8
Balance at end of period	$	49.4		$	79.5		$	49.4		$	79.5

Reclassifications out of accumulated other comprehensive loss are as follows:


	Three Months Ended						Six Months Ended						Affected line items in the consolidated
	June 30,						June 30,						statements of earnings
	2023			2022			2023			2022			and comprehensive earnings
	(Dollars in Millions)
Pension and postretirement benefit plans
Amortization of:
Prior service cost	$	1.6		$	1.2		$	2.8		$	2.1
Actuarial loss		—			1.1			—			1.9
		1.6			2.3			2.8			4.0		Other nonoperating income, net
Tax effect		(0.4	)		(0.6	)		(0.7	)		(1.0	)	Income tax expense
Total	$	1.2		$	1.7		$	2.1		$	3.0

Earnings per Common Share

The numerator for basic and diluted earnings per common share is net earnings attributable to Martin Marietta, reduced by dividends and undistributed earnings attributable to certain of the Company’s stock-based compensation arrangements. If there is a net loss, no amount of the undistributed loss is attributed to unvested participating securities. The denominator for basic earnings per common share is the weighted-average number of common shares outstanding during the period. Diluted earnings per common share is computed assuming that the weighted-average number of common shares is increased by the conversion, using the treasury stock method, of awards to be issued to employees and nonemployee members of the Company’s Board of Directors under certain stock-based compensation arrangements if the conversion is dilutive. For the three and six months ended June 30, 2023 and 2022, the diluted per-share computations reflect the number of common shares outstanding including the number of additional shares that would have been outstanding if the potentially dilutive common shares had been issued.

The following table reconciles the denominator for basic and diluted earnings from continuing operations per common share:


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2023		2022		2023		2022
	(In Millions)
Basic weighted-average common shares outstanding		61.9		62.4		62.0		62.4
Effect of dilutive employee and director awards		0.2		0.1		0.2		0.2
Diluted weighted-average common shares outstanding		62.1		62.5		62.2		62.6

Reclassifications

As of June 30, 2023, the Company combined products and services revenues and freight revenues into total revenues, and combined cost of revenues - products and services and cost of revenues - freight into total cost of revenues on the Company's consolidated statements of earnings and comprehensive earnings. Prior-year information has been reclassified to conform to the current-year presentation. The reclassifications had no impact on the Company’s previously reported results of operations, financial position or cash flows.

Long-Term Debt (Tables)

6 Months Ended

Jun. 30, 2023

Debt Disclosure [Abstract]

Long-Term Debt


	June 30,			December 31,
	2023			2022
	(Dollars in Millions)
0.650% Senior Notes, due 2023 (discharged)	$	700.0		$	699.1
4.250% Senior Notes, due 2024		399.3			398.9
7% Debentures, due 2025		124.7			124.7
3.450% Senior Notes, due 2027		298.5			298.3
3.500% Senior Notes, due 2027		491.9			491.5
2.500% Senior Notes, due 2030		471.0			470.5
2.400% Senior Notes, due 2031		889.0			888.6
6.25% Senior Notes, due 2037		228.4			228.4
4.250% Senior Notes, due 2047		590.3			590.2
3.200% Senior Notes, due 2051		850.0			849.8
Total debt		5,043.1			5,040.0
Less: current maturities		(700.0	)		(699.1	)
Long-term debt	$	4,343.1		$	4,340.9

- Definition

Tabular disclosure of long-debt instruments or arrangements, including identification, terms, features, collateral requirements and other information necessary to a fair presentation. These are debt arrangements that originally required repayment more than twelve months after issuance or greater than the normal operating cycle of the entity, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 69B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481568/470-20-55-69B

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 69E
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481568/470-20-55-69E

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-04(a))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-3

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482925/835-30-45-2

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 1A
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482925/835-30-45-1A

Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-3

Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

Reference 8: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482949/835-30-55-8

Reference 9: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480848/942-470-50-3

Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 8
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-8

Reference 11: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-6

Reference 12: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-7

+ Details

Revenues and Gross Profit - Total Revenues and Gross Profit (Loss) by Product Line (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Product Information [Line Items]
Total Revenues	$ 1,820.8	$ 1,641.7	$ 3,174.9	$ 2,872.5
Gross profit (loss)	560.4	425.2	863.2	581.3
Interproduct Revenues
Product Information [Line Items]
Total Revenues	(121.1)	(102.4)	(208.6)	(191.5)
Corporate
Product Information [Line Items]
Gross profit (loss)	(3.4)	1.6	(1.4)	(6.4)
Building Materials Business
Product Information [Line Items]
Total Revenues	1,740.3	1,560.0	3,011.0	2,713.8
Building Materials Business \| Operating Segments
Product Information [Line Items]
Total Revenues	1,740.3	1,560.0	3,011.0	2,713.8
Gross profit (loss)	536.1	399.1	811.9	537.5
Magnesia Specialties \| Operating Segments
Product Information [Line Items]
Total Revenues	80.5	81.7	163.9	158.7
Gross profit (loss)	27.7	24.5	52.7	50.2
Aggregates \| Building Materials Business \| Operating Segments \| Reportable Subsegments
Product Information [Line Items]
Total Revenues	1,151.4	1,057.6	2,063.3	1,814.2
Gross profit (loss)	370.9	307.3	608.9	410.0
Cement \| Building Materials Business \| Operating Segments \| Reportable Subsegments
Product Information [Line Items]
Total Revenues	197.7	162.5	366.2	300.8
Gross profit (loss)	93.3	50.7	140.4	77.5
Ready Mixed Concrete \| Building Materials Business \| Operating Segments \| Reportable Subsegments
Product Information [Line Items]
Total Revenues	271.4	226.6	491.3	517.8
Gross profit (loss)	35.4	14.6	46.6	36.6
Asphalt and Paving \| Building Materials Business \| Operating Segments \| Reportable Subsegments
Product Information [Line Items]
Total Revenues	240.9	215.7	298.8	272.5
Gross profit (loss)	$ 36.5	$ 26.5	$ 16.0	$ 13.4

Commitments and Contingencies

6 Months Ended

Jun. 30, 2023

Commitments and Contingencies Disclosure [Abstract]

Commitments and Contingencies

Legal and Administrative Proceedings

The Company is engaged in certain legal and administrative proceedings incidental to its normal business activities, including matters relating to environmental protection. The Company considers various factors in assessing the probable outcome of each matter, including but not limited to the nature of existing legal proceedings and claims, the asserted or possible damages, the jurisdiction and venue of the case and whether it is a jury trial, the progress of the case, existing law and precedent, the opinions or views of legal counsel and other advisers, the Company’s experience in similar cases and the experience of other companies, the facts available to the Company at the time of assessment, and how the Company intends to respond to the proceeding or claim. The Company’s assessment of these factors may change over time as proceedings or claims progress. The Company believes the probability is remote that the outcome of any currently pending legal or administrative proceeding will result in a material loss to the Company as a whole, based on currently available facts.

Letters of Credit

In the normal course of business, the Company provides certain third parties with standby letter of credit agreements guaranteeing its payment for certain insurance claims, contract performance and permit requirements. At June 30, 2023, the Company was contingently liable for $26.8 million in letters of credit.

Borrowing Arrangements with Affiliate

The Company is a guarantor with an unconsolidated affiliate for a $15.0 million revolving line of credit agreement with Truist Bank that has a maturity date of March 2024. There were no borrowings outstanding on the line of credit at June 30, 2023. The affiliate has agreed to reimburse and indemnify the Company for any payments and expenses the Company may incur from this agreement. The Company holds a lien on the affiliate’s membership interest in a joint venture as collateral for payment under the revolving line of credit.

In addition, the Company has a $6.0 million interest-only note receivable, due December 31, 2024, outstanding from this unconsolidated affiliate at June 30, 2023 and December 31, 2022.

Long-Term Debt

6 Months Ended

Jun. 30, 2023

Debt Disclosure [Abstract]

Long-Term Debt


	June 30,			December 31,
	2023			2022
	(Dollars in Millions)
0.650% Senior Notes, due 2023 (discharged)	$	700.0		$	699.1
4.250% Senior Notes, due 2024		399.3			398.9
7% Debentures, due 2025		124.7			124.7
3.450% Senior Notes, due 2027		298.5			298.3
3.500% Senior Notes, due 2027		491.9			491.5
2.500% Senior Notes, due 2030		471.0			470.5
2.400% Senior Notes, due 2031		889.0			888.6
6.25% Senior Notes, due 2037		228.4			228.4
4.250% Senior Notes, due 2047		590.3			590.2
3.200% Senior Notes, due 2051		850.0			849.8
Total debt		5,043.1			5,040.0
Less: current maturities		(700.0	)		(699.1	)
Long-term debt	$	4,343.1		$	4,340.9

On September 29, 2022, the Company satisfied and discharged the 2023 Notes. In connection with the satisfaction and discharge, the Company irrevocably deposited funds with Regions Bank, as trustee under the indenture governing the 2023 Notes, in an amount sufficient to satisfy all remaining principal and interest payments on the 2023 Notes. The Company utilized existing cash resources to fund the satisfaction and discharge. As a result of the satisfaction and discharge of the 2023 Notes, the obligations of the Company under the indenture with respect to the 2023 Notes have been terminated, except those provisions of the indenture that, by their terms, survive the satisfaction and discharge. Because the discharge did not represent a legal defeasance, the 2023 Notes remained on the Company’s consolidated balance sheets at June 30, 2023 and December 31, 2022 and continued to accrete to their par value over the period until maturity. Additionally, the related trust assets were included in Restricted investments (to satisfy discharged debt and related interest) on the Company’s consolidated balance sheets at June 30, 2023 and December 31, 2022. On July 17, 2023, Regions Bank satisfied the remaining principal and interest payments and the 2023 Notes are considered repaid in full.

The Company has a credit agreement with JPMorgan Chase Bank, N.A., as Administrative Agent, Deutsche Bank Securities, Inc., PNC Bank, Truist Bank and Wells Fargo Bank, N.A., as Syndication Agents, and the lenders party thereto (the Credit Agreement), which provides for a $800.0 million five-year senior unsecured revolving facility (the Revolving Facility) with a maturity date of December 21, 2027. Borrowings under the Revolving Facility bear interest, at the Company’s option, at rates based upon the Secured Overnight Financing Rate (SOFR) or a base rate, plus, for each rate, a margin determined in accordance with a ratings-based pricing grid. There were no borrowings outstanding under the Credit Agreement as of June 30, 2023 and December 31, 2022. Any outstanding principal amounts, together with interest accrued thereon, are due in full on that maturity date. Available borrowings under the Revolving Facility are reduced by any outstanding letters of credit issued by the Company under the Revolving Facility. At June 30, 2023 and December 31, 2022, the Company had $2.6 million of outstanding letters of credit issued under the Revolving Facility.

The Credit Agreement requires the Company’s ratio of consolidated net debt-to-consolidated earnings before interest, taxes, depreciation, depletion and amortization (EBITDA), as defined by the Revolving Facility, for the trailing-twelve months (the Ratio) to not exceed 3.50x as of the end of any fiscal quarter, provided that the Company may exclude from the Ratio any debt incurred in connection with certain acquisitions during the quarter or three preceding quarters so long as the Ratio calculated without such exclusion does not exceed 4.00x. Additionally, if no amounts are outstanding under the Revolving Facility or the Company's trade receivable securitization facility (discussed below), consolidated debt, as defined, which includes debt for which the Company is a guarantor (see Note 8), shall be reduced in an amount equal to the lesser of $500.0 million or the sum of the Company’s unrestricted cash and temporary investments, for purposes of the covenant calculation. The Company was in compliance with the Ratio at June 30, 2023.

The Company, through a wholly-owned special-purpose subsidiary, has a $400.0 million trade receivable securitization facility (the Trade Receivable Facility), that matures on September 20, 2023. The Trade Receivable Facility, with Truist Bank, Regions Bank, PNC Bank, N.A., MUFG Bank, Ltd., New York Branch, and certain other lenders that may become a party to the facility from time to time, is backed by eligible trade receivables, as defined. Borrowings are limited to the lesser of the facility limit or the borrowing base, as defined. These receivables are originated by the Company and then sold or contributed to the wholly-owned special-purpose subsidiary. The Company continues to be responsible for the servicing and administration of the receivables purchased by the wholly-owned special-purpose subsidiary. Borrowings under the Trade Receivable Facility bear interest at a rate equal to asset-backed commercial paper costs of conduit lenders plus 0.65% for borrowings funded by conduit lenders and Adjusted Term Secured Overnight Financing Rate (Adjusted Term SOFR), as defined, plus 0.7%, subject to change in the event that this rate no longer reflects the lender’s cost of lending, for borrowings funded by all other lenders. The Trade Receivable Facility contains a cross-default provision to the Company’s other debt agreements. Subject to certain conditions, including lenders providing the requisite commitments, the Trade Receivable Facility may be increased to a borrowing base not to exceed $500.0 million. There were no borrowings outstanding under the Trade Receivable Facility at June 30, 2023 and December 31, 2022.

- Definition

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(c))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 470
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//470/tableOfContent

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1C
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1C

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1C
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1C

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1C
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1C

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1E
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1E

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1I
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1I

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1I
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1I

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1I
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1I

+ Details

Consolidated Balance Sheets (Parenthetical) - $ / shares	Jun. 30, 2023	Dec. 31, 2022
Statement of Financial Position [Abstract]
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares outstanding	61,800,000	62,100,000
Preferred stock, par value	$ 0.01	$ 0.01

Revenue Recognition (Tables)

6 Months Ended

Jun. 30, 2023

Revenue from Contract with Customer [Abstract]

Summary of Information About the Company's Contract Balances

The following table presents information about the Company’s contract balances:


	June 30, 2023		December 31, 2022
	(Dollars in Millions)
Costs in excess of billings	$	22.3	$	5.1
Billings in excess of costs	$	6.9	$	10.5

Divestitures, Discontinued Operations and Assets and Liabilities Held for Sale (Detail) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Inventories, net	$ 26.0	$ 31.3
Investment land	18.6	40.6
Other assets	0.2	1.3
Total current assets held for sale	44.8	73.2
Property, plant and equipment	86.8	124.5
Intangible assets, excluding goodwill	208.5	208.5
Operating lease right-of-use assets	2.9	12.1
Goodwill	31.9	31.9
Valuation allowance for loss on sale	(4.5)	(4.5)
Total noncurrent assets held for sale	325.6	372.5
Lease obligations	(0.9)	(4.5)
Total current liabilities held for sale	(0.9)	(4.5)
Lease obligations	0.0	(4.1)
Asset retirement obligations	(17.5)	(17.7)
Total noncurrent liabilities held for sale	(17.5)	(21.8)
Continuing Operations
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Investment land	18.6	40.6
Total current assets held for sale	18.6	40.6
Discontinued Operations
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Inventories, net	26.0	31.3
Other assets	0.2	1.3
Total current assets held for sale	26.2	32.6
Property, plant and equipment	86.8	124.5
Intangible assets, excluding goodwill	208.5	208.5
Operating lease right-of-use assets	2.9	12.1
Goodwill	31.9	31.9
Valuation allowance for loss on sale	(4.5)	(4.5)
Total noncurrent assets held for sale	325.6	372.5
Lease obligations	(0.9)	(4.5)
Total current liabilities held for sale	(0.9)	(4.5)
Lease obligations	0.0	(4.1)
Asset retirement obligations	(17.5)	(17.7)
Total noncurrent liabilities held for sale	$ (17.5)	$ (21.8)

Divestitures, Discontinued Operations and Assets and Liabilities Held for Sale

6 Months Ended

Jun. 30, 2023

Business Combinations [Abstract]

Divestitures, Discontinued Operations and Assets and Liabilities Held for Sale

Divestitures

Since October 1, 2021, the California cement businesses have been classified as assets held for sale on the Company’s consolidated balance sheets; the associated financial results have been reported as discontinued operations on the consolidated statements of earnings. On May 3, 2023, the Company divested its Stockton cement import terminal in California.

On June 30, 2022, the Company completed the sale of the Redding, California cement plant, related cement distribution terminals and 14 California ready mix operations for $235 million in cash. These businesses were previously classified as assets held for sale and their associated financial results were reported as discontinued operations.

On April 1, 2022, the Company divested its Colorado and Central Texas ready-mixed concrete operations to Smyrna Ready Mix Concrete LLC. This transaction optimized the Company’s aggregates-led portfolio and improved its ability to generate more attractive margins over the long term by reducing both business cyclicality and exposure to raw material cost inflation. The transaction resulted in a pretax gain of $151.7 million, which was included in Other operating income, net, and was inclusive of expenses incurred due to the divestiture. The divested operations and the gain on divestiture were all reported in the West Group.

Discontinued Operations

On April 26, 2023, the Company terminated its agreement with CalPortland Company regarding the sale of the Company’s Tehachapi, California cement plant to CalPortland in light of the parties being unable to timely obtain the necessary approval by the U.S. Federal Trade Commission. The Company is exploring the potential sale of the Tehachapi plant to other buyers.

For the three and six months ended June 30, 2023, discontinued operations included the Company's Tehachapi, California cement plant and California ready mixed concrete operations as well as the Stockton, California cement import terminal through the May 3, 2023 divestiture. Discontinued operations for the three and six months ended June 30, 2022 also included the Company's Redding, California cement plant, related cement distribution terminals and 14 California ready mix operations that were sold in June 2022 (hereinafter, the Redding transaction).

Financial results for the Company's discontinued operations are as follows:


	Three Months Ended						Six Months Ended
	June 30,						June 30,
	2023			2022			2023			2022
	(Dollars in Millions)
Total revenues	$	34.5		$	111.7		$	59.2		$	206.4

Pretax (loss) earnings from operations	$	(1.4	)	$	20.5		$	(18.5	)	$	16.4
Pretax gain (loss) on divestiture and sales of assets		2.3			(1.0	)		2.3			(1.0	)
Pretax earnings (loss)		0.9			19.5			(16.2	)		15.4
Income tax expense (benefit)		0.2			6.2			(4.0	)		5.2
Earnings (loss) from discontinued operations, net of income tax expense (benefit)	$	0.7		$	13.3		$	(12.2	)	$	10.2

Total cash provided by operating and investing activities for discontinued operations was $42.5 million for the six months ended June 30, 2023, which included $57.5 million of proceeds from a divestiture and sales of assets and $3.8 million of cash used for capital expenditures. Total cash provided by operating and investing activities for the six months ended June 30, 2022 was $224.2 million, which included $235.0 million of proceeds from divestitures and $13.2 million of cash used for capital expenditures.

Assets and Liabilities Held for Sale

Assets and liabilities held for sale at June 30, 2023 primarily included a cement plant in Tehachapi, California and certain investment properties. At December 31, 2022, assets and liabilities held for sale also included the Stockton, California cement import terminal that was sold in May 2023 and the California ready mixed concrete plants not sold as part of the Redding transaction.

Assets and liabilities held for sale are as follows:


	June 30, 2023								December 31, 2022
	Continuing Operations		Discontinued Operations			Total			Continuing Operations		Discontinued Operations			Total
	(Dollars in Millions)
Inventories, net	$	—	$	26.0		$	26.0		$	—	$	31.3		$	31.3
Investment land		18.6		—			18.6			40.6		—			40.6
Other assets		—		0.2			0.2			—		1.3			1.3
Total current assets held for sale	$	18.6	$	26.2		$	44.8		$	40.6	$	32.6		$	73.2

Property, plant and equipment	$	—	$	86.8		$	86.8		$	—	$	124.5		$	124.5
Intangible assets, excluding goodwill		—		208.5			208.5			—		208.5			208.5
Operating lease right-of-use assets		—		2.9			2.9			—		12.1			12.1
Goodwill		—		31.9			31.9			—		31.9			31.9
Valuation allowance for loss on sale		—		(4.5	)		(4.5	)		—		(4.5	)		(4.5	)
Total noncurrent assets held for sale	$	—	$	325.6		$	325.6		$	—	$	372.5		$	372.5

Lease obligations	$	—	$	(0.9	)	$	(0.9	)	$	—	$	(4.5	)	$	(4.5	)
Total current liabilities held for sale	$	—	$	(0.9	)	$	(0.9	)	$	—	$	(4.5	)	$	(4.5	)

Lease obligations	$	—	$	—		$	—		$	—	$	(4.1	)	$	(4.1	)
Asset retirement obligations		—		(17.5	)		(17.5	)		—		(17.7	)		(17.7	)
Total noncurrent liabilities held for sale	$	—	$	(17.5	)	$	(17.5	)	$	—	$	(21.8	)	$	(21.8	)

Revenues and Gross Profit

6 Months Ended

Jun. 30, 2023

Revenues And Gross Profit [Abstract]

Revenues and Gross Profit

10.

Revenues and Gross Profit

Performance Obligations. Performance obligations are contractual promises to transfer or provide a distinct good or service for a stated price. The Company’s product sales agreements are single-performance obligations that are satisfied at a point in time. Performance obligations within paving service agreements are satisfied over time, primarily ranging from one day to two years. For product and freight revenues, customer payment terms are generally 30 days from invoice date. Customer payments for the paving operations are based on a contractual billing schedule and are due 30 days from invoice date.

Future revenues from unsatisfied performance obligations at June 30, 2023 and 2022 were $357.8 million and $322.5 million, respectively, where the remaining periods to complete these obligations ranged from one month to 28 months and one month to 23 months, respectively.

Service Revenues. Service revenues, which include paving services located in California and Colorado, were $107.9 million and $95.0 million for the three months ended June 30, 2023 and 2022, respectively, and are reported in the West Group. Service revenues for the six months ended June 30, 2023 and 2022 were $134.3 million and $113.3 million, respectively.

Contract Balances. Costs in excess of billings relate to the conditional right to consideration for completed contractual performance and are contract assets on the consolidated balance sheets. Costs in excess of billings are reclassified to accounts receivable when the right to consideration becomes unconditional. Billings in excess of costs relate to customers invoiced in advance of contractual performance and are contract liabilities on the consolidated balance sheets. The following table presents information about the Company’s contract balances:


	June 30, 2023		December 31, 2022
	(Dollars in Millions)
Costs in excess of billings	$	22.3	$	5.1
Billings in excess of costs	$	6.9	$	10.5

Revenues recognized from the beginning balance of contract liabilities for the three months ended June 30, 2023 and 2022 were $4.8 million and $4.5 million, respectively, and for the six months ended June 30, 2023 and 2022 were $8.2 million and $6.6 million, respectively.

Retainage, which primarily relates to the paving services, represents amounts that have been billed to customers but payment withheld until final acceptance of the performance obligation by the customer. Retainage, which is included in Other current assets on the Company’s consolidated balance sheets, was $11.9 million and $13.4 million at June 30, 2023 and December 31, 2022, respectively.


	Three Months Ended						Six Months Ended
	June 30,						June 30,
	2023			2022			2023			2022
	(Dollars in Millions)
Total revenues:
Building Materials business:
Aggregates	$	1,151.4		$	1,057.6		$	2,063.3		$	1,814.2
Cement		197.7			162.5			366.2			300.8
Ready mixed concrete		271.4			226.6			491.3			517.8
Asphalt and paving services		240.9			215.7			298.8			272.5
Less: interproduct revenues		(121.1	)		(102.4	)		(208.6	)		(191.5	)
Total Building Materials business		1,740.3			1,560.0			3,011.0			2,713.8
Magnesia Specialties		80.5			81.7			163.9			158.7
Total	$	1,820.8		$	1,641.7		$	3,174.9		$	2,872.5

Gross profit (loss):
Building Materials business:
Aggregates	$	370.9		$	307.3		$	608.9		$	410.0
Cement		93.3			50.7			140.4			77.5
Ready mixed concrete		35.4			14.6			46.6			36.6
Asphalt and paving services		36.5			26.5			16.0			13.4
Total Building Materials business		536.1			399.1			811.9			537.5
Magnesia Specialties		27.7			24.5			52.7			50.2
Corporate		(3.4	)		1.6			(1.4	)		(6.4	)
Total	$	560.4		$	425.2		$	863.2		$	581.3

Inventories, Net (Tables)

6 Months Ended

Jun. 30, 2023

Inventory Disclosure [Abstract]

Schedule of Inventories Net


	June 30,			December 31,
	2023			2022
	(Dollars in Millions)
Finished products	$	1,060.9		$	932.4
Products in process		21.0			24.8
Raw materials		87.3			71.7
Supplies and expendable parts		169.3			153.1
Total inventories		1,338.5			1,182.0
Less: allowances		(383.8	)		(308.3	)
Inventories, net	$	954.7		$	873.7

Significant Accounting Policies (Policies)

6 Months Ended

Jun. 30, 2023

Accounting Policies [Abstract]

Organization

The Company’s Building Materials business includes two reportable segments: the East Group and the West Group.


BUILDING MATERIALS BUSINESS (continuing operations only)
Reportable Segments	East Group	West Group
Operating Locations	Alabama, Florida, Georgia, Indiana, Iowa, Kansas, Kentucky, Maryland, Minnesota, Missouri, Nebraska, North Carolina, Ohio, Pennsylvania, South Carolina, Tennessee, Virginia, West Virginia, Nova Scotia and The Bahamas	Arizona, Arkansas, California, Colorado, Louisiana, Oklahoma, Texas, Utah, Washington and Wyoming

Product Lines	Aggregates and Asphalt	Aggregates, Cement, Ready Mixed Concrete, Asphalt and Paving

Basis of Presentation and Use of Estimates

Revenue Recognition

Restricted Cash


	June 30,		December 31,
	2023		2022
	(Dollars in Millions)
Cash and cash equivalents	$	421.5	$	358.0
Restricted cash		—		0.8
Total cash, cash equivalents and restricted cash presented in the consolidated statements of cash flows	$	421.5	$	358.8

Restricted Investments

Consolidated Comprehensive Earnings (Loss) and Accumulated Other Comprehensive Loss

Consolidated comprehensive earnings (loss) attributable to Martin Marietta is as follows:


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2023		2022		2023		2022
	(Dollars in Millions)
Net earnings attributable to Martin Marietta	$	348.3	$	366.5	$	469.7	$	387.9
Other comprehensive earnings (loss), net of tax		1.7		1.2		2.8		(30.5	)
Consolidated comprehensive earnings attributable to Martin Marietta	$	350.0	$	367.7	$	472.5	$	357.4

The components of the changes in accumulated other comprehensive loss, net of tax, are as follows:


	(Dollars in Millions)
	Pension and Postretirement Benefit Plans			Foreign Currency			Accumulated Other Comprehensive Loss
	Three Months Ended June 30, 2023
Balance at beginning of period	$	(35.5	)	$	(1.9	)	$	(37.4	)
Other comprehensive earnings before reclassifications, net of tax		—			0.5			0.5
Amounts reclassified from accumulated other comprehensive loss, net of tax		1.2			—			1.2
Other comprehensive earnings, net of tax		1.2			0.5			1.7
Balance at end of period	$	(34.3	)	$	(1.4	)	$	(35.7	)

	Three Months Ended June 30, 2022
Balance at beginning of period	$	(129.7	)	$	0.4		$	(129.3	)
Other comprehensive earnings (loss) before reclassifications, net of tax		0.4			(0.9	)		(0.5	)
Amounts reclassified from accumulated other comprehensive loss, net of tax		1.7			—			1.7
Other comprehensive earnings (loss), net of tax		2.1			(0.9	)		1.2
Balance at end of period	$	(127.6	)	$	(0.5	)	$	(128.1	)


	(Dollars in Millions)
	Pension and Postretirement Benefit Plans			Foreign Currency			Accumulated Other Comprehensive Loss
	Six Months Ended June 30, 2023
Balance at beginning of period	$	(36.5	)	$	(2.0	)	$	(38.5	)
Other comprehensive earnings before reclassifications, net of tax		0.1			0.6			0.7
Amounts reclassified from accumulated other comprehensive loss, net of tax		2.1			—			2.1
Other comprehensive earnings, net of tax		2.2			0.6			2.8
Balance at end of period	$	(34.3	)	$	(1.4	)	$	(35.7	)

	Six Months Ended June 30, 2022
Balance at beginning of period	$	(97.6	)	$	—		$	(97.6	)
Other comprehensive loss before reclassifications, net of tax		(33.0	)		(0.5	)		(33.5	)
Amounts reclassified from accumulated other comprehensive loss, net of tax		3.0			—			3.0
Other comprehensive loss, net of tax		(30.0	)		(0.5	)		(30.5	)
Balance at end of period	$	(127.6	)	$	(0.5	)	$	(128.1	)

Changes in net noncurrent deferred tax assets related to accumulated other comprehensive loss are as follows:


	Pension and Postretirement Benefit Plans
	Three Months Ended						Six Months Ended
	June 30,						June 30,
	2023			2022			2023			2022
	(Dollars in Millions)
Balance at beginning of period	$	49.8		$	80.2		$	50.1		$	69.7
Tax effect of other comprehensive (earnings) loss		(0.4	)		(0.7	)		(0.7	)		9.8
Balance at end of period	$	49.4		$	79.5		$	49.4		$	79.5

Reclassifications out of accumulated other comprehensive loss are as follows:


	Three Months Ended						Six Months Ended						Affected line items in the consolidated
	June 30,						June 30,						statements of earnings
	2023			2022			2023			2022			and comprehensive earnings
	(Dollars in Millions)
Pension and postretirement benefit plans
Amortization of:
Prior service cost	$	1.6		$	1.2		$	2.8		$	2.1
Actuarial loss		—			1.1			—			1.9
		1.6			2.3			2.8			4.0		Other nonoperating income, net
Tax effect		(0.4	)		(0.6	)		(0.7	)		(1.0	)	Income tax expense
Total	$	1.2		$	1.7		$	2.1		$	3.0

Earnings per Common Share

The following table reconciles the denominator for basic and diluted earnings from continuing operations per common share:


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2023		2022		2023		2022
	(In Millions)
Basic weighted-average common shares outstanding		61.9		62.4		62.0		62.4
Effect of dilutive employee and director awards		0.2		0.1		0.2		0.2
Diluted weighted-average common shares outstanding		62.1		62.5		62.2		62.6

Reclassifications

- Definition

Disclosure of accounting policy for investment in financial asset.

+ References + Details

- Definition

Disclosure of accounting policy for revenue from contract with customer.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-17

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 19
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-19

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-18

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-18

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 20
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-20

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 20
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-20

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 20
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-20

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 20
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-20

Reference 9: http://www.xbrl.org/2003/role/exampleRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (e)
-SubTopic 10
-Topic 235
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483426/235-10-50-4

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Topic 606
-Publisher FASB
-URI https://asc.fasb.org//606/tableOfContent

+ Details

Divestitures, Discontinued Operations and Assets and Liabilities Held for Sale - Additional Information (Detail) $ in Millions		6 Months Ended
	Apr. 01, 2022 USD ($)	Jun. 30, 2023 USD ($)	Jun. 30, 2022 USD ($) Plant
Business Acquisition [Line Items]
Cash used for operating and investing activities for discontinued operations		$ 42.5	$ 224.2
Revenues			235.0
Proceeds from Divestiture and sale of assets		57.5	235.0
Capital expenditures		$ 3.8	$ 13.2
Business combination number of California ready mix operations \| Plant			14
Colorado and Central Texas
Business Acquisition [Line Items]
Pretax gain	$ 151.7

Significant Accounting Policies - Reconciliation of Cash, Cash Equivalents and Restricted Cash (Detail) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022	Jun. 30, 2022	Dec. 31, 2021
Restricted Cash and Cash Equivalents [Abstract]
Cash and cash equivalents	$ 421.5	$ 358.0
Restricted cash	0.0	0.8
Total cash, cash equivalents and restricted cash presented in the consolidated statements of cash flows	$ 421.5	$ 358.8	$ 772.1	$ 258.9

Significant Accounting Policies - Basic and Diluted Earnings from Continuing Operations Per Common Share (Detail) - shares shares in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Earnings Per Share [Abstract]
Basic weighted-average common shares outstanding	61.9	62.4	62.0	62.4
Effect of dilutive employee and director awards	0.2	0.1	0.2	0.2
Diluted weighted-average common shares outstanding	62.1	62.5	62.2	62.6

Long-Term Debt - Long-Term Debt (Detail) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Total debt	$ 5,043.1	$ 5,040.0
Less: Current maturities	(700.0)	(699.1)
Long-term debt	4,343.1	4,340.9
0.650% Senior Notes, Due 2023 (discharged)
Debt Instrument [Line Items]
Total debt	700.0	699.1
4.250% Senior Notes, Due 2024
Debt Instrument [Line Items]
Total debt	399.3	398.9
7% Debentures, Due 2025
Debt Instrument [Line Items]
Total debt	124.7	124.7
3.450% Senior Notes, Due 2027
Debt Instrument [Line Items]
Total debt	298.5	298.3
3.500% Senior Notes, Due 2027
Debt Instrument [Line Items]
Total debt	491.9	491.5
2.500% Senior Notes, Due 2030
Debt Instrument [Line Items]
Total debt	471.0	470.5
2.400% Senior Notes, Due 2031
Debt Instrument [Line Items]
Total debt	889.0	888.6
6.25% Senior Notes, Due 2037
Debt Instrument [Line Items]
Total debt	228.4	228.4
4.250% Senior Notes, Due 2047
Debt Instrument [Line Items]
Total debt	590.3	590.2
3.200% Senior Notes, Due 2051
Debt Instrument [Line Items]
Total debt	$ 850.0	$ 849.8

Segments

6 Months Ended

Jun. 30, 2023

Segment Reporting [Abstract]

Segments

The Building Materials business contains two reportable segments: the East Group and the West Group. The Company also has a Magnesia Specialties segment. The Company’s evaluation of performance and allocation of resources are based primarily on earnings from operations. Consolidated earnings from operations include total revenues less cost of revenues; selling, general and administrative expenses; acquisition and integration expenses; other operating income and expenses, net; and exclude interest expense; other nonoperating income and expenses, net; and income tax expense. Corporate loss from operations primarily includes depreciation; expenses for corporate administrative functions; acquisition and integration expenses; and other nonrecurring income and expenses not attributable to operations of the Company's other operating segments. All long-term debt and related interest expense are reported in Corporate.


	Three Months Ended						Six Months Ended
	June 30,						June 30,
	2023			2022			2023			2022
	(Dollars in Millions)
Total revenues:
East Group	$	735.1		$	674.5		$	1,264.7		$	1,093.3
West Group		1,005.2			885.5			1,746.3			1,620.5
Total Building Materials business		1,740.3			1,560.0			3,011.0			2,713.8
Magnesia Specialties		80.5			81.7			163.9			158.7
Total	$	1,820.8		$	1,641.7		$	3,174.9		$	2,872.5

Earnings (Loss) from operations:
East Group	$	227.5		$	210.6		$	336.4		$	238.5
West Group		239.6			274.5			334.3			317.6
Total Building Materials business		467.1			485.1			670.7			556.1
Magnesia Specialties		23.3			20.3			43.9			41.8
Corporate		(27.1	)		(26.8	)		(55.3	)		(59.5	)
Total	$	463.3		$	478.6		$	659.3		$	538.4

- Definition

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-22

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 15
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-15

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 31
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-31

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-32

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-42

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-32

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 40
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-40

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//280/tableOfContent

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 26
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-26

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 34
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-34

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 41
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-41

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 21
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-21

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 21
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-21

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-32

+ Details

Segments - Additional Information (Detail) $ in Millions	6 Months Ended	12 Months Ended
Segments - Additional Information (Detail) $ in Millions	Jun. 30, 2023 Segment	Dec. 31, 2022 USD ($)
Segment Reporting Information [Line Items]
Reportable business segments \| Segment	2
West Group [Member]
Segment Reporting Information [Line Items]
Nonrecurring gains on divested assets \| $		$ 151.7

Long-Term Debt - Additional Information (Detail) $ in Millions	6 Months Ended
	Jun. 30, 2023 USD ($)	Dec. 31, 2022 USD ($)
Debt Instrument [Line Items]
Credit facility commitment	$ 800.0
Maximum consolidated debt reduction for unrestricted cash and temporary investments	500.0
Outstanding letters of credit	$ 26.8
Revolving Facility
Debt Instrument [Line Items]
Debt instrument maturity period	Dec. 21, 2027
Outstanding borrowing under credit facility	$ 0.0	$ 0.0
Senior unsecured revolving facility, maturity period	5 years
Outstanding letters of credit	$ 2.6	2.6
Maximum \| Including Acquisition Bridge Debt
Debt Instrument [Line Items]
Debt covenant	3.5
Maximum \| Excluding Acquisition Bridge Debt
Debt Instrument [Line Items]
Debt covenant	4
Trade Receivable Facility
Debt Instrument [Line Items]
Line of credit, trade receivable securitization facility	$ 400.0
Debt instrument maturity period	Sep. 20, 2023
Outstanding borrowing under credit facility	$ 0.0	$ 0.0
Trade Receivable Facility \| Maximum
Debt Instrument [Line Items]
Credit facility commitment	$ 500.0
Trade Receivable Facility \| Conduit Lenders
Debt Instrument [Line Items]
Basis spread on variable rate	0.65%
Trade Receivable Facility \| SOFR
Debt Instrument [Line Items]
Basis spread on variable rate	0.70%

Significant Accounting Policies - Comprehensive Earnings (Loss) Attributable to Martin Marietta Materials Incorporated (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Statement of Comprehensive Income [Abstract]
Net Income (Loss)	$ 348.3	$ 366.5	$ 469.7	$ 387.9
Other comprehensive earnings (loss), net of tax	1.7	1.2	2.8	(30.5)
Consolidated comprehensive earnings attributable to Martin Marietta	$ 350.0	$ 367.7	$ 472.5	$ 357.4

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

+ Details

Divestitures, Discontinued Operations and Assets and Liabilities Held for Sale (Tables)

6 Months Ended

Jun. 30, 2023

Business Combinations [Abstract]

Summary of Discontinued Operations and Assets and Liabilities Held for Sale

Financial results for the Company's discontinued operations are as follows:


	Three Months Ended						Six Months Ended
	June 30,						June 30,
	2023			2022			2023			2022
	(Dollars in Millions)
Total revenues	$	34.5		$	111.7		$	59.2		$	206.4

Pretax (loss) earnings from operations	$	(1.4	)	$	20.5		$	(18.5	)	$	16.4
Pretax gain (loss) on divestiture and sales of assets		2.3			(1.0	)		2.3			(1.0	)
Pretax earnings (loss)		0.9			19.5			(16.2	)		15.4
Income tax expense (benefit)		0.2			6.2			(4.0	)		5.2
Earnings (loss) from discontinued operations, net of income tax expense (benefit)	$	0.7		$	13.3		$	(12.2	)	$	10.2

Assets and liabilities held for sale are as follows:


	June 30, 2023								December 31, 2022
	Continuing Operations		Discontinued Operations			Total			Continuing Operations		Discontinued Operations			Total
	(Dollars in Millions)
Inventories, net	$	—	$	26.0		$	26.0		$	—	$	31.3		$	31.3
Investment land		18.6		—			18.6			40.6		—			40.6
Other assets		—		0.2			0.2			—		1.3			1.3
Total current assets held for sale	$	18.6	$	26.2		$	44.8		$	40.6	$	32.6		$	73.2

Property, plant and equipment	$	—	$	86.8		$	86.8		$	—	$	124.5		$	124.5
Intangible assets, excluding goodwill		—		208.5			208.5			—		208.5			208.5
Operating lease right-of-use assets		—		2.9			2.9			—		12.1			12.1
Goodwill		—		31.9			31.9			—		31.9			31.9
Valuation allowance for loss on sale		—		(4.5	)		(4.5	)		—		(4.5	)		(4.5	)
Total noncurrent assets held for sale	$	—	$	325.6		$	325.6		$	—	$	372.5		$	372.5

Lease obligations	$	—	$	(0.9	)	$	(0.9	)	$	—	$	(4.5	)	$	(4.5	)
Total current liabilities held for sale	$	—	$	(0.9	)	$	(0.9	)	$	—	$	(4.5	)	$	(4.5	)

Lease obligations	$	—	$	—		$	—		$	—	$	(4.1	)	$	(4.1	)
Asset retirement obligations		—		(17.5	)		(17.5	)		—		(17.7	)		(17.7	)
Total noncurrent liabilities held for sale	$	—	$	(17.5	)	$	(17.5	)	$	—	$	(21.8	)	$	(21.8	)

- Definition

Tabular disclosure of information related to a disposal group. Includes, but is not limited to, a discontinued operation, disposal classified as held-for-sale or disposed of by means other than sale or disposal of an individually significant component.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-SubTopic 10
-Topic 360
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482099/360-10-50-3

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 11
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483475/205-20-45-11

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3A
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483499/205-20-50-3A

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 4A
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483499/205-20-50-4A

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 4B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483499/205-20-50-4B

Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5A
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483499/205-20-50-5A

Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483499/205-20-50-5B

Reference 8: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5C
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483499/205-20-50-5C

Reference 9: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5D
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483499/205-20-50-5D

Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483499/205-20-50-7

Reference 11: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 360
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3A
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482099/360-10-50-3A

Reference 12: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-SubTopic 20
-Topic 205
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483499/205-20-50-1

Reference 13: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483499/205-20-50-3

+ Details

Revenues and Gross Profit - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
Revenue Recognition [Line Items]
Performance obligations, description of timing			Performance obligations within paving service agreements are satisfied over time, primarily ranging from one day to two years. For product and freight revenues, customer payment terms are generally 30 days from invoice date. Customer payments for the paving operations are based on a contractual billing schedule and are due 30 days from invoice date.
Product and freight revenues customer payment terms			30 days
Customer payments terms based on contractual billing			30 days
Future revenues from unsatisfied performance obligations	$ 357.8	$ 322.5	$ 357.8	$ 322.5
Service revenues	1,820.8	1,641.7	3,174.9	2,872.5
Revenue recognized from contract liabilities	4.8	4.5	8.2	6.6
Retainage on contracts	11.9		11.9		$ 13.4
Service \| CALIFORNIA and COLORADO \| West Group
Revenue Recognition [Line Items]
Service revenues	$ 107.9	$ 95.0	$ 134.3	$ 113.3
Minimum \| Service
Revenue Recognition [Line Items]
Performance obligations, period			1 day
Maximum \| Service
Revenue Recognition [Line Items]
Performance obligations, period			2 years

Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Cash Flows from Operating Activities:
Consolidated net earnings	$ 470.2	$ 387.7
Adjustments to reconcile consolidated net earnings to net cash provided by operating activities:
Depreciation, depletion and amortization	253.1	256.6
Stock-based compensation expense	27.7	24.5
Gain on sales of assets, divestitures and extinguishment of debt	(16.3)	(173.9)
Deferred income taxes, net	0.7	(32.7)
Other items, net	(4.5)	(3.4)
Changes in operating assets and liabilities, net of effects of acquisitions and divestitures:
Accounts receivable, net	(196.2)	(252.6)
Inventories, net	(92.2)	(79.5)
Accounts payable	44.5	68.5
Other assets and liabilities, net	31.5	91.0
Net Cash Provided by Operating Activities	518.5	286.2
Cash Flows from Investing Activities:
Additions to property, plant and equipment	(293.4)	(220.7)
Acquisitions, net of cash acquired	0.0	11.0
Proceeds from sales of assets and divestitures	95.5	644.4
Investments in life insurance contracts, net	4.8	1.8
Other investing activities, net	(4.2)	(3.0)
Net Cash (Used for) Provided by Investing Activities	(197.3)	433.5
Cash Flows from Financing Activities:
Repayments of debt	0.0	(47.7)
Payments on finance lease obligations	(8.4)	(7.3)
Dividends paid	(82.5)	(77.0)
Repurchases of common stock	(150.0)	(50.0)
Distributions to owners of noncontrolling interest	(0.5)	0.0
Proceeds from exercise of stock options	0.8	0.6
Shares withheld for employees' income tax obligations	(17.9)	(25.1)
Net Cash Used for Financing Activities	(258.5)	(206.5)
Net Increase in Cash, Cash Equivalents and Restricted Cash	62.7	513.2
Cash, Cash Equivalents and Restricted Cash, beginning of period	358.8	258.9
Cash, Cash Equivalents and Restricted Cash, end of period	$ 421.5	$ 772.1

Pension and Postretirement Benefits

6 Months Ended

Jun. 30, 2023

Retirement Benefits [Abstract]

Pension and Postretirement Benefits

The net periodic benefit cost (credit) for pension and postretirement benefits includes the following components:


	Pension						Postretirement Benefits
	Three Months Ended June 30,
	2023			2022			2023			2022
	(Dollars in Millions)
Service cost	$	9.3		$	14.0		$	—		$	—
Interest cost		14.6			11.9			0.2			0.1
Expected return on assets		(20.3	)		(22.5	)		—			—
Amortization of:
Prior service cost (credit)		1.7			1.4			(0.1	)		(0.2	)
Actuarial loss (gain)		0.2			1.2			(0.2	)		(0.1	)
Net periodic benefit cost (credit)	$	5.5		$	6.0		$	(0.1	)	$	(0.2	)


	Pension						Postretirement Benefits
	Six Months Ended June 30,
	2023			2022			2023			2022
	(Dollars in Millions)
Service cost	$	16.4		$	24.0		$	—		$	—
Interest cost		25.7			20.6			0.2			0.2
Expected return on assets		(35.7	)		(38.7	)		—			—
Amortization of:
Prior service cost (credit)		2.9			2.5			(0.1	)		(0.4	)
Actuarial loss (gain)		0.3			2.0			(0.3	)		(0.1	)
Net periodic benefit cost (credit)	$	9.6		$	10.4		$	(0.2	)	$	(0.3	)

The components of net periodic benefit cost (credit), other than service cost, are included in the line item Other nonoperating income, net, in the consolidated statements of earnings and comprehensive earnings. Based on the roles of the employees, service cost is included in the Cost of revenues or Selling, general and administrative expenses line items in the consolidated statements of earnings and comprehensive earnings.

- Definition

The entire disclosure for retirement benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 70
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480794/715-70-50-1

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480482/715-20-55-17

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)(iv)(03)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)(i)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (q)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (l)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//715/tableOfContent

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)(iii)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (o)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (p)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (r)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (r)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480126/715-20-S99-2

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 60
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480266/715-60-50-3

+ Details

Segments - Financial Data for Continuing Operations for Company's Reportable Business Segments (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Segment Reporting Information [Line Items]
Total Revenues	$ 1,820.8	$ 1,641.7	$ 3,174.9	$ 2,872.5
Earnings (Loss) from operations	463.3	478.6	659.3	538.4
Building Materials Business
Segment Reporting Information [Line Items]
Total Revenues	1,740.3	1,560.0	3,011.0	2,713.8
Earnings (Loss) from operations	467.1	485.1	670.7	556.1
Operating Segments \| Building Materials Business East Group
Segment Reporting Information [Line Items]
Total Revenues	735.1	674.5	1,264.7	1,093.3
Earnings (Loss) from operations	227.5	210.6	336.4	238.5
Operating Segments \| Building Materials Business West Group
Segment Reporting Information [Line Items]
Total Revenues	1,005.2	885.5	1,746.3	1,620.5
Earnings (Loss) from operations	239.6	274.5	334.3	317.6
Operating Segments \| Magnesia Specialties
Segment Reporting Information [Line Items]
Total Revenues	80.5	81.7	163.9	158.7
Earnings (Loss) from operations	23.3	20.3	43.9	41.8
Operating Segments \| Building Materials Business
Segment Reporting Information [Line Items]
Total Revenues	1,740.3	1,560.0	3,011.0	2,713.8
Corporate
Segment Reporting Information [Line Items]
Earnings (Loss) from operations	$ (27.1)	$ (26.8)	$ 55.3	$ (59.5)

- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 924
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 11.L)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479941/924-10-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-5

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 30
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-30

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-42

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-22

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-32

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 40
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-40

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-22

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-32

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 41
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-41

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-4

+ Details

Supplemental Cash Flow Information

6 Months Ended

Jun. 30, 2023

Supplemental Cash Flow Elements [Abstract]

Supplemental Cash Flow Information

11.

Supplemental Cash Flow Information

Noncash investing and financing activities are as follows:


	Six Months Ended
	June 30,
	2023		2022
	(Dollars in Millions)
Accrued liabilities for purchases of property, plant and equipment	$	63.1	$	27.3
Remeasurement of operating lease right-of-use assets	$	1.4	$	(3.5	)
Remeasurement of finance lease right-of-use assets	$	—	$	(6.4	)
Right-of-use assets obtained in exchange for new operating lease liabilities	$	28.6	$	13.0
Right-of-use assets obtained in exchange for new finance lease liabilities	$	16.3	$	7.0
Acquisition of assets through asset exchange	$	5.2	$	—

Supplemental disclosures of cash flow information are as follows:


	Six Months Ended
	June 30,
	2023		2022
	(Dollars in Millions)
Cash paid for interest, net of capitalized amount	$	79.6	$	84.3
Cash paid for income taxes, net of refunds	$	83.0	$	42.9

Income Taxes - Additional Information (Detail)	6 Months Ended
Income Taxes - Additional Information (Detail)	Jun. 30, 2023	Jun. 30, 2022
Income Tax Disclosure [Abstract]
Effective income tax rates for continuing operations	20.90%	22.60%

Divestitures, Discontinued Operations and Assets and Liabilities Held for Sale - Summary of Discontinued Operations (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Discontinued Operations and Disposal Groups [Abstract]
Total revenues	$ 34.5	$ 111.7	$ 0.0	$ 206.4
Pretax (loss) earnings from operations	(1.4)	20.5	(18.5)	16.4
Pretax gain (loss) on divestiture and sales of assets	2.3	(1.0)	2.3	(1.0)
Pretax (loss) earnings	0.9	19.5	(16.2)	15.4
Income tax expense (benefit)	0.2	6.2	(0.0)	5.2
Earnings (loss) from discontinued operations, net of income tax expense (benefit)	$ 0.7	$ 13.3	$ (12.2)	$ 10.2

- Definition

Amount before tax of income (loss) from a discontinued operation. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

+ References + Details

- Definition

Amount of tax expense (benefit) related to a discontinued operation. Includes, but is not limited to, tax expense (benefit) related to income (loss) from operations during the phase-out period, tax expense (benefit) related to gain (loss) on disposal, tax expense (benefit) related to gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and tax expense (benefit) related to adjustments of a prior period gain (loss) on disposal.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-10

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 6.I.7)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479360/740-10-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482659/740-20-45-2

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 3A
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483475/205-20-45-3A

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5B
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483499/205-20-50-5B

Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5C
-Subparagraph (b)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483499/205-20-50-5C

Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 3B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483475/205-20-45-3B

Reference 8: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483475/205-20-45-4

Reference 9: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483499/205-20-50-1

+ Details

- Definition

Amount after tax of income (loss) from a discontinued operation attributable to the parent. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

+ References + Details

Long-Term Debt - Long-Term Debt (Parenthetical) (Detail)	6 Months Ended	12 Months Ended
	Jun. 30, 2023	Dec. 31, 2022
0.650% Senior Notes, Due 2023 (discharged)
Debt Instrument [Line Items]
Maturity year	2023	2023
Interest rate on notes	0.65%	0.65%
4.250% Senior Notes, Due 2024
Debt Instrument [Line Items]
Maturity year	2024
Interest rate on notes	4.25%
7% Debentures, Due 2025
Debt Instrument [Line Items]
Maturity year	2025
Interest rate on notes	7.00%
3.450% Senior Notes, Due 2027
Debt Instrument [Line Items]
Maturity year	2027
Interest rate on notes	3.45%
3.500% Senior Notes, Due 2027
Debt Instrument [Line Items]
Maturity year	2027
Interest rate on notes	3.50%
2.500% Senior Notes, Due 2030
Debt Instrument [Line Items]
Maturity year	2030
Interest rate on notes	2.50%
2.400% Senior Notes, Due 2031
Debt Instrument [Line Items]
Maturity year	2031
Interest rate on notes	2.40%
6.25% Senior Notes, Due 2037
Debt Instrument [Line Items]
Maturity year	2037
Interest rate on notes	6.25%
4.250% Senior Notes, Due 2047
Debt Instrument [Line Items]
Maturity year	2047
Interest rate on notes	4.25%
3.200% Senior Notes, Due 2051
Debt Instrument [Line Items]
Maturity year	2051
Interest rate on notes	3.20%

Significant Accounting Policies - Noncurrent Deferred Tax Assets Recorded in Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Equity [Abstract]
Balance at beginning of period	$ 49.8	$ 80.2	$ 50.1	$ 69.7
Tax effect of other comprehensive (earnings) loss	(0.4)	(0.7)	(0.7)	9.8
Balance at end of period	$ 49.4	$ 79.5	$ 49.4	$ 79.5

Pension and Postretirement Benefits (Tables)

6 Months Ended

Jun. 30, 2023

Retirement Benefits [Abstract]

Schedule of Components of Net Periodic Benefit Cost (Credit)

The net periodic benefit cost (credit) for pension and postretirement benefits includes the following components:


	Pension						Postretirement Benefits
	Three Months Ended June 30,
	2023			2022			2023			2022
	(Dollars in Millions)
Service cost	$	9.3		$	14.0		$	—		$	—
Interest cost		14.6			11.9			0.2			0.1
Expected return on assets		(20.3	)		(22.5	)		—			—
Amortization of:
Prior service cost (credit)		1.7			1.4			(0.1	)		(0.2	)
Actuarial loss (gain)		0.2			1.2			(0.2	)		(0.1	)
Net periodic benefit cost (credit)	$	5.5		$	6.0		$	(0.1	)	$	(0.2	)


	Pension						Postretirement Benefits
	Six Months Ended June 30,
	2023			2022			2023			2022
	(Dollars in Millions)
Service cost	$	16.4		$	24.0		$	—		$	—
Interest cost		25.7			20.6			0.2			0.2
Expected return on assets		(35.7	)		(38.7	)		—			—
Amortization of:
Prior service cost (credit)		2.9			2.5			(0.1	)		(0.4	)
Actuarial loss (gain)		0.3			2.0			(0.3	)		(0.1	)
Net periodic benefit cost (credit)	$	9.6		$	10.4		$	(0.2	)	$	(0.3	)