View Filing Data

Document and Entity Information - shares	6 Months Ended
Document and Entity Information - shares	Jun. 30, 2015	Jul. 31, 2015
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2015
Document Fiscal Year Focus	2015
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 Common Stock, Shares Outstanding		67,001,255

Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2014
Current Assets:
Cash and cash equivalents	$ 44,169	$ 108,651	$ 34,329
Accounts receivable, net	497,468	421,001	343,784
Inventories, net	479,856	484,919	348,168
Current deferred income tax benefits	234,594	244,638	72,413
Assets held for sale	426,495
Other current assets	82,667	29,607	78,007
Total Current Assets	1,765,249	1,288,816	876,701
Property, plant and equipment	5,421,449	5,691,676	3,970,472
Allowances for depreciation, depletion and amortization	(2,371,926)	(2,288,906)	(2,195,098)
Net property, plant and equipment	3,049,523	3,402,770	1,775,374
Goodwill	2,065,882	2,068,799	616,621
Other noncurrent assets	104,056	108,802	40,451
Total Assets	7,499,654	7,464,392	3,356,043
Current Liabilities:
Bank overdraft		183
Accounts payable	201,235	202,476	139,442
Accrued salaries, benefits and payroll taxes	27,590	36,576	17,393
Pension and postretirement benefits	8,133	6,953	2,356
Accrued insurance and other taxes	57,078	58,356	33,014
Current maturities of long-term debt and short-term facilities	15,966	14,336	12,404
Accrued interest	16,165	16,136	7,386
Other current liabilities	37,667	61,632	32,730
Total Current Liabilities	363,834	396,648	244,725
Long-term debt	1,642,035	1,571,059	1,072,397
Pension, postretirement and postemployment benefits	272,461	249,333	82,662
Noncurrent deferred income taxes	756,526	734,583	275,279
Other noncurrent liabilities	154,365	160,021	113,981
Total Liabilities	3,189,221	3,111,644	1,789,044
Equity:
Common stock, par value $0.01 per share	668	671	463
Preferred stock, par value $0.01 per share
Additional paid-in capital	3,274,098	3,243,619	456,989
Accumulated other comprehensive loss	(112,814)	(106,159)	(42,141)
Retained earnings	1,146,821	1,213,035	1,149,388
Total Shareholders' Equity	4,308,773	4,351,166	1,564,699
Noncontrolling interests	1,660	1,582	2,300
Total Equity	4,310,433	4,352,748	1,566,999
Total Liabilities and Equity	7,499,654	7,464,392	3,356,043
Operating Permits
Current Assets:
Intangibles, net	447,702	499,487	16,829
Other Intangible Assets
Current Assets:
Intangibles, net	$ 67,242	$ 95,718	$ 30,067

Consolidated Balance Sheets (Parenthetical) - $ / shares	Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2014
Statement Of Financial Position [Abstract]
Common stock, par value	$ 0.01	$ 0.01	$ 0.01
Preferred stock, par value	$ 0.01	$ 0.01	$ 0.01

Consolidated Statements of Earnings and Comprehensive Earnings - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Income Statement [Abstract]
Net Sales	$ 850,249	$ 601,937	$ 1,482,124	$ 981,615
Freight and delivery revenues	71,170	67,288	130,641	116,240
Total revenues	921,419	669,225	1,612,765	1,097,855
Cost of sales	650,096	466,335	1,207,710	820,177
Freight and delivery costs	71,170	67,288	130,641	116,240
Total cost of revenues	721,266	533,623	1,338,351	936,417
Gross Profit	200,153	135,602	274,414	161,438
Selling, general & administrative expenses	56,783	36,566	106,233	70,813
Acquisition-related expenses, net	2,092	5,280	3,696	15,060
Other operating expenses and (income), net	4,294	(2,485)	1,930	(4,779)
Earnings from Operations	136,984	96,241	162,555	80,344
Interest expense	19,087	12,947	38,418	25,149
Other nonoperating (income) and expenses, net	(3,011)	(292)	(2,118)	3,171
Earnings from continuing operations before taxes on income	120,908	83,586	126,255	52,024
Income tax expense	38,929	23,906	38,117	15,482
Earnings from Continuing Operations	81,979	59,680	88,138	36,542
Loss on discontinued operations, net of related tax benefit of $24 and $25, respectively		(56)		(70)
Consolidated net earnings	81,979	59,624	88,138	36,472
Less: Net earnings (loss) attributable to noncontrolling interests	(41)	(103)	(73)	1,432
Net Earnings Attributable to Martin Marietta Materials, Inc.	81,938	59,521	88,065	37,904
Net Earnings (Loss) Attributable to Martin Marietta Materials, Inc.:
Earnings from continuing operations	81,938	59,577	88,065	37,974
Loss from discontinued operations		(56)		(70)
Net Earnings Attributable to Martin Marietta Materials, Inc.	81,938	59,521	88,065	37,904
Consolidated Comprehensive Earnings: (See Note 1)
Earnings attributable to Martin Marietta Materials, Inc.	75,847	60,124	81,410	39,877
Earnings (Loss) attributable to noncontrolling interests	43	104	78	(1,430)
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	$ 75,890	$ 60,228	$ 81,488	$ 38,447
Net Earnings (Loss) Attributable to Martin Marietta Materials, Inc. per common share
Basic from continuing operations attributable to common shareholders	$ 1.23	$ 1.28	$ 1.30	$ 0.81
Earnings Per Share, Basic, Total	1.23	1.28	1.30	0.81
Diluted from continuing operations attributable to common shareholders	1.22	1.27	1.30	0.81
Earnings Per Share, Diluted, Total	$ 1.22	$ 1.27	$ 1.30	$ 0.81
Weighted-Average Common Shares Outstanding:
Basic	67,373	46,395	67,392	46,355
Diluted	67,633	46,529	67,654	46,477
Cash Dividends Per Common Share	$ 0.40	$ 0.40	$ 0.80	$ 0.80

Consolidated Statements of Earnings and Comprehensive Earnings (Parenthetical) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2014	Jun. 30, 2014
Income Statement [Abstract]
Loss on discontinued operations, related tax benefit	$ 24	$ 25

- 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 + Details

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Cash Flows from Operating Activities:
Consolidated net earnings	$ 88,138	$ 36,472
Adjustments to reconcile consolidated net earnings to net cash provided by operating activities:
Depreciation, depletion and amortization	134,958	86,147
Stock-based compensation expense	7,524	4,370
Gains on divestitures and sales of assets	(853)	(1,747)
Deferred income taxes	33,906	(6,433)
Excess tax benefits from stock-based compensation transactions	(55)	(1,922)
Other items, net	(341)	3,227
Changes in operating assets and liabilities, net of effects of acquisitions and divestitures:
Accounts receivable, net	(76,061)	(98,911)
Inventories, net	(27,661)	(4,269)
Accounts payable	(3,416)	35,842
Other assets and liabilities, net	(29,070)	17,587
Net Cash Provided by Operating Activities	127,069	70,363
Cash Flows from Investing Activities:
Additions to property, plant and equipment	(127,990)	(84,737)
Acquisitions, net	(10,713)	(117)
Proceeds from divestitures and sales of assets	1,972	2,154
Repayments from affiliate	1,808	529
Payment of railcar construction advances	(25,234)	(14,513)
Reimbursement of railcar construction advances	25,234	14,513
Net Cash Used for Investing Activities	(134,923)	(82,171)
Cash Flows from Financing Activities:
Borrowings of long-term debt	80,000	100,000
Repayments of long-term debt	(8,144)	(46,417)
Payments on capital lease obligations	(1,831)	(1,052)
Debt issuance costs		(881)
Change in bank overdraft	(183)	(2,556)
Dividends paid	(54,285)	(37,254)
Purchase of remaining interest in existing subsidiaries		(19,604)
Issuances of common stock	27,760	9,542
Repurchases of common stock	(100,000)
Excess tax benefits from stock-based compensation transactions	55	1,922
Net Cash (Used for) Provided by Financing Activities	(56,628)	3,700
Net Decrease in Cash and Cash Equivalents	(64,482)	(8,108)
Cash and Cash Equivalents, beginning of period	108,651	42,437
Cash and Cash Equivalents, end of period	44,169	34,329
Supplemental Disclosures of Cash Flow Information:
Cash paid for interest	35,447	25,173
Cash paid for income taxes	$ 24,334	$ 3,511

Consolidated Statement of Total Equity - 6 months ended Jun. 30, 2015 - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Loss	Retained Earnings	Total Shareholders' Equity	Noncontrolling Interests
Beginning Balance at Dec. 31, 2014	$ 4,352,748	$ 671	$ 3,243,619	$ (106,159)	$ 1,213,035	$ 4,351,166	$ 1,582
Beginning Balance (in shares) at Dec. 31, 2014		67,293,000
Consolidated net earnings	88,138				88,065	88,065	73
Other comprehensive (loss) earnings, net of tax	(6,650)			(6,655)		(6,655)	5
Dividends declared	(54,285)				(54,285)	(54,285)
Issuances of common stock for stock award plans	22,958	$ 3	22,955			22,958
Issuances of common stock for stock award plans (in shares)		368,000
Repurchases of common stock	(100,000)	$ (6)			(99,994)	(100,000)
Repurchases of common stock (in shares)		(670,000)
Stock-based compensation expense	7,524		7,524			7,524
Ending Balance at Jun. 30, 2015	$ 4,310,433	$ 668	$ 3,274,098	$ (112,814)	$ 1,146,821	$ 4,308,773	$ 1,660
Ending Balance (in shares) at Jun. 30, 2015		66,991,000

Significant Accounting Policies

6 Months Ended

Jun. 30, 2015

Accounting Policies [Abstract]

Significant Accounting Policies

1.	Significant Accounting Policies

Organization

Martin Marietta Materials, Inc. (the “Corporation” or “Martin Marietta”) is engaged principally in the construction aggregates business. The aggregates product line accounted for 58% of 2014 consolidated net sales and includes crushed stone, sand and gravel, and is used for construction of highways and other infrastructure projects, and in the nonresidential and residential construction industries. Aggregates products are also used in the railroad, agricultural, utility and environmental industries. These aggregates products, along with the Corporation’s aggregates-related downstream product lines, which accounted for 25% of 2014 consolidated net sales and include asphalt products, ready mixed concrete and road paving construction services, are sold and shipped from a network of more than 400 quarries, distribution facilities and plants to customers in 32 states, Canada, the Bahamas and the Caribbean Islands. The aggregates and aggregates-related downstream product lines are reported collectively as the “Aggregates business”.

The Corporation currently conducts the Aggregates business through three reportable segments: the Mid-America Group, the Southeast Group and the West Group.

AGGREGATES BUSINESS

Reportable Segments

Mid-America Group

Southeast Group

West Group

Operating Locations

Indiana, Iowa,

northern Kansas, Kentucky, Maryland, Minnesota, Missouri,

eastern Nebraska, North Carolina, Ohio,

South Carolina,

Virginia, Washington and

West Virginia

Alabama, Florida, Georgia, Mississippi, Tennessee, Nova Scotia and the Bahamas

Arkansas, Colorado, southern Kansas,

Louisiana, western Nebraska, Nevada, Oklahoma, Texas, Utah

and Wyoming

The Corporation has a Cement segment, which was acquired July 1, 2014 and accounted for 8% of 2014 consolidated net sales, with production facilities located in Midlothian, Texas, south of Dallas/Fort Worth; Hunter, Texas, south of San Antonio; and Oro Grande, near Los Angeles, California. The cement business produces Portland and specialty cements, such as masonry and oil well cements. Similar to the Aggregates business, cement is used in infrastructure projects, nonresidential and residential construction, and the railroad, agricultural, utility and environmental industries. The high calcium limestone reserves used as a raw material are a part of owned property adjacent to each of the plants. The Corporation also operates cement terminals, a packaging facility and cement grinding facility at the Crestmore plant near Riverside, California.

The Corporation has a Magnesia Specialties segment with manufacturing facilities in Manistee, Michigan and Woodville, Ohio. The Magnesia Specialties segment, which accounted for 9% of 2014 consolidated net sales, produces magnesia-based chemicals products used in industrial, agricultural and environmental applications and dolomitic lime sold primarily to customers in the steel industry.

1.	Significant Accounting Policies (continued)

Basis of Presentation

The accompanying unaudited consolidated financial statements of the Corporation have been prepared in accordance with generally accepted accounting principles 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 Corporation has continued to follow the accounting policies set forth in the audited consolidated financial statements and related notes thereto included in the Corporation’s Annual Report on Form 10-K for the year ended December 31, 2014. In the opinion of management, the interim consolidated financial information provided herein reflects all adjustments, consisting of normal recurring accruals, necessary for a fair presentation of the results of operations, financial position and cash flows for the interim periods. The consolidated results of operations for the six months ended June 30, 2015 are not indicative of the results expected for other interim periods or the full year. The consolidated balance sheet at December 31, 2014 has been derived from the audited consolidated financial statements at that date but does not include all of the information and notes required by generally accepted accounting principles 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 Corporation’s Annual Report on Form 10-K for the year ended December 31, 2014.

Revenue Recognition Standard

The FASB issued an accounting standard update that amends the accounting guidance on revenue recognition. The new standard intends to provide a more robust framework for addressing revenue issues, improve comparability of revenue recognition practices and improve disclosure requirements. The new standard is effective for interim and annual reporting periods beginning after December 15, 2017 and can be applied on a full retrospective or modified retrospective approach. The Corporation is currently evaluating the impact of the provisions of the new standard, and at this time does not expect the impact to be material to its consolidated results of operations.

Consolidated Comprehensive Earnings/Loss and Accumulated Other Comprehensive Loss

Consolidated comprehensive earnings/loss for the Corporation consist of consolidated net earnings or loss; adjustments for the funded status of pension and postretirement benefit plans; foreign currency translation adjustments; and the amortization of the value of terminated forward starting interest rate swap agreements into interest expense, and are presented in the Corporation’s consolidated statements of earnings and comprehensive earnings.

Comprehensive earnings attributable to Martin Marietta is as follows:

	Three Months Ended					Six Months Ended
	June 30,					June 30,
	2015			2014		2015			2014
	(Dollars in Thousands)
Net earnings attributable to Martin Marietta Materials, Inc.	$	81,938		$	59,521	$	88,065		$	37,904
Other comprehensive (loss) earnings, net of tax		(6,091	)		603		(6,655	)		1,973
Comprehensive earnings attributable to Martin Marietta Materials, Inc.	$	75,847		$	60,124	$	81,410		$	39,877

1.	Significant Accounting Policies (continued)

Consolidated Comprehensive Earnings/Loss and Accumulated Other Comprehensive Loss (continued)

Comprehensive earnings (loss) attributable to noncontrolling interests, consisting of net earnings or loss and adjustments for the funded status of pension and postretirement benefit plans, is as follows:

	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2015		2014		2015		2014
	(Dollars in Thousands)
Net earnings (loss) attributable to noncontrolling interests	$	41	$	103	$	73	$	(1,432	)
Other comprehensive earnings, net of tax		2		1		5		2
Comprehensive earnings (loss) attributable to noncontrolling interests	$	43	$	104	$	78	$	(1,430	)

Accumulated other comprehensive loss consists of unrealized gains and losses related to the funded status of pension and postretirement benefit plans; foreign currency translation; and the unamortized value of terminated forward starting interest rate swap agreements, and is presented on the Corporation’s consolidated balance sheets.

Changes in accumulated other comprehensive loss, net of tax, are as follows:

	(Dollars in Thousands)
						Unamortized
						Value of
						Terminated			Accumulated
	Pension and					Forward Starting			Other
	Postretirement			Foreign		Interest Rate			Comprehensive
	Benefit Plans			Currency		Swap			Loss
	Three Months Ended June 30, 2015
Balance at beginning of period	$	(105,151	)	$	990	$	(2,562	)	$	(106,723	)
Other comprehensive (loss) earnings before reclassifications, net of tax		(10,670	)		229		—			(10,441	)
Amounts reclassified from accumulated other comprehensive loss, net of tax		4,158			—		192			4,350
Other comprehensive (loss) earnings, net of tax		(6,512	)		229		192			(6,091	)
Balance at end of period	$	(111,663	)	$	1,219	$	(2,370	)	$	(112,814	)

	Three Months Ended June 30, 2014
Balance at beginning of period	$	(44,267	)	$	4,816	$	(3,293	)	$	(42,744	)
Other comprehensive (loss) earnings before reclassifications, net of tax		(426	)		842		—			416
Amounts reclassified from accumulated other comprehensive earnings, net of tax		8			—		179			187
Other comprehensive (loss) earnings, net of tax		(418	)		842		179			603
Balance at end of period	$	(44,685	)	$	5,658	$	(3,114	)	$	(42,141	)

1.	Significant Accounting Policies (continued)

Consolidated Comprehensive Earnings/Loss and Accumulated Other Comprehensive Loss (continued)

The other comprehensive loss before reclassifications for pension and postretirement benefit plans is net of tax benefit of $6,793,000 and $276,000 for the three months ended June 30, 2015 and 2014, respectively.

	(Dollars in Thousands)
							Unamortized
							Value of
							Terminated			Accumulated
	Pension and						Forward Starting			Other
	Postretirement			Foreign			Interest Rate			Comprehensive
	Benefit Plans			Currency			Swap			Loss
	Six Months Ended June 30, 2015
Balance at beginning of period	$	(106,688	)	$	3,278		$	(2,749	)	$	(106,159	)
Other comprehensive loss before reclassifications, net of tax		(10,845	)		(2,059	)		—			(12,904	)
Amounts reclassified from accumulated other comprehensive (loss) earnings, net of tax		5,870			—			379			6,249
Other comprehensive (loss) earnings, net of tax		(4,975	)		(2,059	)		379			(6,655	)
Balance at end of period	$	(111,663	)	$	1,219		$	(2,370	)	$	(112,814	)

	Six Months Ended June 30, 2014
Balance at beginning of period	$	(44,549	)	$	3,902		$	(3,467	)	$	(44,114	)
Other comprehensive (loss) earnings before reclassifications, net of tax		(430	)		1,756			—			1,326
Amounts reclassified from accumulated other comprehensive earnings, net of tax		294			—			353			647
Other comprehensive (loss) earnings, net of tax		(136	)		1,756			353			1,973
Balance at end of period	$	(44,685	)	$	5,658		$	(3,114	)	$	(42,141	)

The other comprehensive loss before reclassifications for pension and postretirement benefit plans is net of tax benefit of $6,904,000 and $280,000 for the six months ended June 30, 2015 and 2014, respectively.

1.	Significant Accounting Policies (continued)

Consolidated Comprehensive Earnings/Loss and Accumulated Other Comprehensive Loss (continued)

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

	(Dollars in Thousands)
	Pension and Postretirement Benefit Plans		Unamortized Value of Terminated Forward Starting Interest Rate Swap			Net Noncurrent Deferred Tax Assets

	Three Months Ended June 30, 2015
Balance at beginning of period	$	67,552	$	1,679		$	69,231
Tax effect of other comprehensive earnings		4,073		(125	)		3,948
Balance at end of period	$	71,625	$	1,554		$	73,179

	Three Months Ended June 30, 2014
Balance at beginning of period	$	29,016	$	2,155		$	31,171
Tax effect of other comprehensive earnings		271		(116	)		155
Balance at end of period	$	29,287	$	2,039		$	31,326

	Six Months Ended June 30, 2015
Balance at beginning of period	$	68,568	$	1,799		$	70,367
Tax effect of other comprehensive earnings		3,057		(245	)		2,812
Balance at end of period	$	71,625	$	1,554		$	73,179

	Six Months Ended June 30, 2014
Balance at beginning of period	$	29,198	$	2,269		$	31,467
Tax effect of other comprehensive earnings		89		(230	)		(141	)
Balance at end of period	$	29,287	$	2,039		$	31,326

1.	Significant Accounting Policies (continued)

Consolidated Comprehensive Earnings/Loss and Accumulated Other Comprehensive Loss (continued)

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 and
	2015			2014			2015			2014			comprehensive earnings
	(Dollars in Thousands)
Pension and postretirement benefit plans
Amortization of:
Prior service credit	$	(469	)	$	(791	)	$	(939	)	$	(1,404	)
Actuarial loss		7,274			804			10,546			1,889
		6,805			13			9,607			485		Cost of sales; Selling, general and administrative expenses
Tax benefit		(2,647	)		(5	)		(3,737	)		(191	)	Income tax benefit
	$	4,158		$	8		$	5,870		$	294

Unamortized value of terminated forward starting interest rate swap
Additional interest expense	$	317		$	295		$	624		$	583		Interest expense
Tax benefit		(125	)		(116	)		(245	)		(230	)	Income tax benefit
	$	192		$	179		$	379		$	353

Earnings per Common Share

The numerator for basic and diluted earnings (loss) per common share is net earnings/loss attributable to Martin Marietta reduced by dividends and undistributed earnings attributable to the Corporation’s unvested restricted stock awards and incentive stock awards. 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 are 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 Corporation’s Board of Directors under certain stock-based compensation arrangements if the conversion is dilutive. For the three and six months ended June 30, 2015 and 2014, the diluted per-share computations reflect a change in the number of common shares outstanding to include the number of additional shares that would have been outstanding if the potentially dilutive common shares had been issued.

1.	Significant Accounting Policies (continued)

Earnings per Common Share (continued)

The following table reconciles the numerator and denominator for basic and diluted earnings per common share:

	Three Months Ended						Six Months Ended
	June 30,						June 30,
	2015			2014			2015		2014
	(In Thousands)
Net earnings from continuing operations attributable to Martin Marietta Materials, Inc.	$	81,938		$	59,577		$	88,065	$	37,974
Less: Distributed and undistributed earnings attributable to unvested awards		(876	)		246			403		154
Basic and diluted net earnings available to common shareholders from continuing operations attributable to Martin Marietta Materials, Inc.		82,814			59,331			87,662		37,820
Basic and diluted net loss available to common shareholders from discontinued operations		—			(56	)		—		(70	)
Basic and diluted net earnings available to common shareholders attributable to Martin Marietta Materials, Inc.	$	82,814		$	59,275		$	87,662	$	37,750

Basic weighted-average common shares outstanding		67,373			46,395			67,392		46,355
Effect of dilutive employee and director awards		260			134			262		122
Diluted weighted-average common shares outstanding		67,633			46,529			67,654		46,477

Business Combinations and Assets Held For Sale

6 Months Ended

Jun. 30, 2015

Business Combinations [Abstract]

Business Combinations and Assets Held for Sale

2.	Business Combinations and Assets Held for Sale

The Corporation acquired Texas Industries, Inc. (“TXI”) on July 1, 2014. For the three and six months ended June 30, 2015, total revenues of $243,837,000 and $467,896,000, respectively, and earnings from operations of $25,242,000 and $33,936,000, respectively, were attributable to TXI operations and included in the Corporation’s consolidated statements of earnings.

Acquisition-related expenses, net, associated with TXI were $2,135,000 and $3,586,000 for the three and six months ended June 30, 2015, respectively. For the three and six months ended June 30, 2014, acquisition-related expenses, net, associated with TXI were $5,265,000 and $14,991,000, respectively.

2.	Business Combinations and Assets Held for Sale (continued)

Unaudited Pro Forma Financial Information

The unaudited pro forma financial information in the table below summarizes the combined consolidated results of operations for the Corporation and TXI as though the companies were combined as of January 1, 2014. Transactions between Martin Marietta and TXI during the periods presented in the pro forma financial statements have been eliminated as if Martin Marietta and TXI were consolidated affiliates during the periods. Financial information for periods prior to the July 1, 2014 actual acquisition date included in the pro forma earnings does not reflect any cost savings or associated costs to achieve such savings from operating efficiencies, synergies, debt refinancing, utilization of TXI net operating loss carryforwards or other restructuring that resulted from the combination.

The unaudited pro forma financial information for the three and six months ended June 30, 2014 includes TXI’s historical operating results for the three and six months ended May 31, 2014 (due to a difference in TXI’s historical reporting periods).

The pro forma financial statements do not purport to project the future financial position or operating results of the combined company. The pro forma financial information presented below is for informational purposes only and is not indicative of the results of operations that would have been achieved if the acquisitions had taken place as of January 1, 2014.

	Three Months Ended		Six Months Ended
	June 30, 2014		June 30, 2014
	(Dollars in Thousands)
Net sales	$	831,760	$	1,395,150
Earnings (Loss) from continuing operations attributable to controlling interest	$	68,313	$	(11,474	)

Assets Held for Sale

At June 30, 2015, the Corporation classified assets related to the California cement operations as assets held for sale, and primarily included the cement plant, mobile equipment and intangible assets. In addition, assets held for sale also included inventory. These assets are reported within the Cement Group segment in Note 10.

There are liabilities that will be transferred as part of the sale, which are reported in other current liabilities on the consolidated balance sheet.

Goodwill

6 Months Ended

Jun. 30, 2015

Goodwill And Intangible Assets Disclosure [Abstract]

Goodwill

The following table shows the changes in goodwill by reportable segment and in total:

	(Dollars in Thousands)
	Mid-America			Southeast		West
	Group			Group		Group		Cement			Total
	Six Months Ended June 30, 2015
Balance at January 1, 2015	$	282,117		$	50,346	$	852,436	$	883,900		$	2,068,799
Adjustments to purchase price allocations		—			—		15,882		(18,978	)		(3,096	)
Acquisitions		—			—		893		—			893
Divestitures		(714	)		—		—		—			(714	)
Balance at June 30, 2015	$	281,403		$	50,346	$	869,211	$	864,922		$	2,065,882

Inventories, Net

6 Months Ended

Jun. 30, 2015

Inventory Disclosure [Abstract]

Inventories, Net

4.	Inventories, Net

	June 30,			December 31,			June 30,
	2015			2014			2014
	(Dollars in Thousands)
Finished products	$	427,298		$	413,766		$	358,759
Products in process and raw materials		60,498			65,250			20,732
Supplies and expendable parts		112,587			125,092			65,287
		600,383			604,108			444,778
Less: Allowances		(120,527	)		(119,189	)		(96,610	)
Total	$	479,856		$	484,919		$	348,168

Long-Term Debt

6 Months Ended

Jun. 30, 2015

Debt Disclosure [Abstract]

Long-Term Debt

5.	Long-Term Debt

	June 30,			December 31,			June 30,
	2015			2014			2014
	(Dollars in Thousands)
6.6% Senior Notes, due 2018	$	299,243		$	299,123		$	299,006
7% Debentures, due 2025		124,516			124,500			124,485
6.25% Senior Notes, due 2037		228,208			228,184			228,165
4.25 % Senior Notes, due 2024		395,511			395,309			—
Floating Rate Notes, due 2017, interest rate of 1.38% and 1.33% at June 30, 2015 and December 31, 2014, respectively		299,108			298,869			—
Term Loan Facility, due 2018, interest rate of 1.69% at June 30, 2015; 1.67% at December 31, 2014; and 1.65% at June 30, 2014		230,167			236,258			242,350
Revolving Facility, interest rate of 1.40% at June 30, 2014		—			—			40,000
Trade Receivable Facility, interest rate of 0.88% and 0.75% at June 30, 3015 and 2014, respectively		80,000			—			150,000
Other notes		1,248			3,152			795
Total debt		1,658,001			1,585,395			1,084,801
Less: Current maturities		(15,966	)		(14,336	)		(12,404	)
Long-term debt	$	1,642,035		$	1,571,059		$	1,072,397

The Corporation, through a wholly-owned special purpose subsidiary, has a $250,000,000 trade receivable securitization facility (the “Trade Receivable Facility”), which matures on September 30, 2016. The Trade Receivable Facility, with SunTrust Bank, Regions Bank, PNC Bank, N.A. and certain other lenders that may become a party to the facility from time to time, is backed by eligible trade receivables, as defined, of $450,791,000, $369,575,000 and $311,792,000 at June 30, 2015, December 31, 2014 and June 30, 2014, respectively. These receivables are originated by the Corporation and then sold to the wholly-owned special purpose subsidiary by the Corporation. The Corporation 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 one-month LIBOR plus 0.7% and are limited to the lesser of the facility limit or the borrowing base, as defined, of $377,688,000, $313,428,000 and $258,787,000 at June 30, 2015, December 31, 2014 and June 30, 2014, respectively. The Trade Receivable Facility contains a cross-default provision to the Corporation’s other debt agreements.

5.	Long-Term Debt (continued)

The Corporation’s Credit Agreement, which provides a $250,000,000 senior unsecured term loan (the “Term Loan Facility”) and a $350,000,000 five-year senior unsecured revolving facility (the “Revolving Facility”), requires the Corporation’s ratio of consolidated debt to consolidated earnings before interest, taxes, depreciation, depletion and amortization (“EBITDA”), as defined by the Credit Agreement, for the trailing twelve months (the “Ratio”) to not exceed 3.50x as of the end of any fiscal quarter, provided that the Corporation may exclude from the Ratio debt incurred in connection with certain acquisitions for a period of 180 days so long as the Corporation, as a consequence of such specified acquisition, does not have its rating on long-term unsecured debt fall below BBB by Standard & Poor’s or Baa2 by Moody’s and the Ratio calculated without such exclusion does not exceed 3.75x. Additionally, if no amounts are outstanding under both the Revolving Facility and the Trade Receivable Facility, consolidated debt, including debt for which the Corporation is a co-borrower, may be reduced by the Corporation’s unrestricted cash and cash equivalents in excess of $50,000,000, such reduction not to exceed $200,000,000, for purposes of the covenant calculation.

In 2014, the Corporation amended the Credit Agreement to ensure the impact of the business combination with TXI does not impair liquidity available under the Term Loan Facility and the Revolving Facility. The amendment adjusts consolidated EBITDA to add back fees, costs or expenses relating to the TXI business combination incurred on or prior to the closing of the combination not to exceed $95,000,000; any integration or similar costs or expenses related to the TXI business combination incurred in any period prior to the second anniversary of the closing of the TXI business combination not to exceed $70,000,000; and any make-whole fees incurred in connection with the redemption of TXI’s 9.25% senior notes due 2020. The Corporation was in compliance with this Ratio at June 30, 2015.

Available borrowings under the Revolving Facility are reduced by any outstanding letters of credit issued by the Corporation under the Revolving Facility. At June 30, 2015, December 31, 2014 and June 30, 2014, the Corporation had $2,507,000 of outstanding letters of credit issued under the Revolving Facility.

Accumulated other comprehensive loss includes the unamortized value of terminated forward starting interest rate swap agreements. For the three and six months ended June 30, 2015, the Corporation recognized $317,000 and $624,000, respectively, as additional interest expense. For the three and six months ended June 30, 2014, the Corporation recognized $295,000 and $583,000, respectively, as additional interest expense. The ongoing amortization of the terminated value of the forward starting interest rate swap agreements will increase annual interest expense by approximately $1,200,000 until the maturity of the 6.6% Senior Notes in 2018.

Financial Instruments

6 Months Ended

Jun. 30, 2015

Fair Value Disclosures [Abstract]

Financial Instruments

6.	Financial Instruments

The Corporation’s financial instruments include cash equivalents, accounts receivable, notes receivable, bank overdraft, accounts payable, publicly-registered long-term notes, debentures and other long-term debt.

Cash equivalents are placed primarily in money market funds, money market demand deposit accounts and Eurodollar time deposits. The Corporation’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.

6.	Financial Instruments (continued)

Accounts receivable are due from a large number of customers, primarily in the construction industry, and are dispersed across wide geographic and economic regions. However, accounts receivable are more heavily concentrated in certain states (namely, Texas, Colorado, North Carolina, Iowa and Georgia). The estimated fair values of accounts receivable approximate their carrying amounts due to the short-term nature of the receivables.

Notes receivable are primarily promissory notes with customers and are not publicly traded. Management estimates that the fair value of notes receivable approximates the carrying amount. The estimated fair values of notes receivable approximate their carrying amounts due to the short-term nature of the receivables.

The bank overdraft represents amounts to be funded to financial institutions for checks that have cleared the bank. The estimated fair value of the bank overdraft approximates its carrying value due to the short-term nature of the overdraft.

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

The carrying values and fair values of the Corporation’s long-term debt were $1,658,001,000 and $1,729,511,000, respectively, at June 30, 2015; $1,585,395,000 and $1,680,584,000, respectively, at December 31, 2014; and $1,084,801,000 and $1,168,302,000, respectively, at June 30, 2014. The estimated fair value of the publicly-registered long-term notes was estimated based on Level 1 of the fair value hierarchy using quoted market prices. The fair value of the Notes was based on Level 2 of the fair value hierarchy using quoted market prices for similar debt instruments. The estimated fair value of other borrowings, which primarily represents variable-rate debt, approximates its carrying amount as the interest rates reset periodically.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Income Taxes

6 Months Ended

Jun. 30, 2015

Income Tax Disclosure [Abstract]

Income Taxes

7.	Income Taxes

	Six Months Ended June 30,
	2015			2014
Estimated effective income tax rate:
Continuing operations		30.2	%		29.8	%
Discontinued operations		—			26.4	%
Consolidated overall		30.2	%		29.8	%

The Corporation’s effective income tax rate reflects the effect of federal and state income taxes and the impact of differences in book and tax accounting arising from the net permanent benefits associated with the statutory depletion deduction for mineral reserves and the domestic production deduction. The effective income tax rate for discontinued operations reflect the tax effects of individual operations’ transactions and are not indicative of the Corporation’s overall effective income tax rate.

The Corporation records interest accrued in relation to unrecognized tax benefits as income tax expense. Penalties, if incurred, are recorded as operating expenses in the consolidated statements of earnings and comprehensive earnings.

Pension and Postretirement Benefits

6 Months Ended

Jun. 30, 2015

Compensation And Retirement Disclosure [Abstract]

Pension and Postretirement Benefits

8.	Pension and Postretirement Benefits

The estimated components of the recorded net periodic benefit cost (credit) for pension and postretirement benefits are as follows:

	Three Months Ended June 30,
	Pension						Postretirement Benefits
	2015			2014			2015			2014
	(Dollars in Thousands)
Service cost	$	5,513		$	3,092		$	34		$	51
Interest cost		8,213			5,624			229			305
Expected return on assets		(8,887	)		(6,677	)		—			—
Amortization of:
Prior service cost (credit)		101			96			(570	)		(887	)
Actuarial loss (gain)		7,351			877			(77	)		(73	)
Special termination benefit		1,206			—			—			—
Net periodic benefit cost (credit)	$	13,497		$	3,012		$	(384	)	$	(604	)

	Six Months Ended June 30,
	Pension						Postretirement Benefits
	2015			2014			2015			2014
	(Dollars in Thousands)
Service cost	$	11,505		$	7,131		$	68		$	93
Interest cost		16,575			12,971			464			559
Expected return on assets		(18,190	)		(15,400	)		—			—
Amortization of:
Prior service cost (credit)		211			223			(1,150	)		(1,627	)
Actuarial loss (gain)		10,700			2,022			(154	)		(133	)
Special termination benefit		1,462			—			—			—
Net periodic benefit cost (credit)	$	22,263		$	6,947		$	(772	)	$	(1,108	)

Commitments and Contingencies

6 Months Ended

Jun. 30, 2015

Commitments And Contingencies Disclosure [Abstract]

Commitments and Contingencies

9.	Commitments and Contingencies

Legal and Administrative Proceedings

The Corporation is engaged in certain legal and administrative proceedings incidental to its normal business activities. In the opinion of management and counsel, based upon currently-available facts, it is remote that the ultimate outcome of any litigation and other proceedings, including those pertaining to environmental matters, relating to the Corporation and its subsidiaries, will have a material adverse effect on the overall results of the Corporation’s operations, its cash flows or its financial position.

Borrowing Arrangements with Affiliate

The Corporation is a co-borrower with an unconsolidated affiliate for a $25,000,000 revolving line of credit agreement with BB&T Bank. The affiliate has agreed to reimburse and indemnify the Corporation for any payments and expenses the Corporation may incur from this agreement. The Corporation holds a lien on the affiliate’s membership interest in a joint venture as collateral for payment under the revolving line of credit.

In 2013, the Corporation loaned $3,402,000 to this unconsolidated affiliate to repay in full the outstanding balance of the affiliate’s loan with Bank of America, N.A. in 2013 and entered into a loan agreement with the affiliate for monthly repayment of principal and interest of that loan amount. The loan was repaid in full during first quarter 2015. As of December 31, 2014 and June 30, 2014, the amounts due from the affiliate related to this loan was $1,808,000 and $2,455,000, respectively.

In addition, the Corporation has a $6,000,000 outstanding loan due from this unconsolidated affiliate as of June 30, 2015, December 31, 2014 and June 30, 2014.

Employees

Approximately 12% of the Corporation’s employees are represented by a labor union. All such employees are hourly employees. The Corporation maintains collective bargaining agreements relating to the union employees with the Aggregates business, Cement and Magnesia Specialties segments. For the Cement segment located in California and Texas, 100% of its hourly employees at the Oro Grande cement plant and Crestmore clinker grinding facility, both located in California, are represented by labor unions. The Oro Grande collective bargaining agreement expires June 2016, and the Crestmore collective bargaining agreement expires in August 2016. For the Magnesia Specialties segment located in Manistee, Michigan and Woodville, Ohio, 100% of its hourly employees are represented by labor unions. The Manistee collective bargaining agreement expires in August 2019, and the Woodville collective bargaining agreement expires in May 2018.

Business Segments

6 Months Ended

Jun. 30, 2015

Segment Reporting [Abstract]

Business Segments

10.	Business Segments

The Aggregates business contains three reportable business segments: Mid-America Group, Southeast Group and West Group. The Corporation also has Cement and Magnesia Specialties segments. Corporate loss from operations primarily includes depreciation on capitalized interest, expenses for certain corporate administrative functions, business development and integration expenses, unallocated corporate expenses and other nonrecurring and/or non-operational adjustments. Intersegment sales represent net sales from one segment to another segment.

10.	Business Segments (Continued)

The following tables display selected financial data for continuing operations for the Corporation’s reportable business segments. Total revenues and net sales in the table below, as well as the consolidated statements of earnings and comprehensive earnings, do not include intersegment sales as these sales are eliminated.

	Three Months Ended						Six Months Ended
	June 30,						June 30,
	2015			2014			2015			2014
	(Dollars in Thousands)
Total revenues:
Mid-America Group	$	257,649		$	240,526		$	398,482		$	356,235
Southeast Group		81,518			75,168			146,195			134,988
West Group		411,235			286,811			731,807			477,598
Total Aggregates Business		750,402			602,505			1,276,484			968,821
Cement		105,899			—			207,999			—
Magnesia Specialties		65,118			66,720			128,282			129,034
Total	$	921,419		$	669,225		$	1,612,765		$	1,097,855

Net sales:
Mid-America Group	$	237,415		$	218,703		$	367,120		$	325,236
Southeast Group		76,483			70,725			136,253			126,106
West Group		375,489			250,589			662,570			411,004
Total Aggregates Business		689,387			540,017			1,165,943			862,346
Cement		100,405			—			196,970			—
Magnesia Specialties		60,457			61,920			119,211			119,269
Total	$	850,249		$	601,937		$	1,482,124		$	981,615

Earnings (Loss) from operations:
Mid-America Group	$	66,894		$	57,283		$	62,691		$	45,517
Southeast Group		4,818			(1,302	)		3,269			(7,413	)
West Group		49,177			30,873			63,676			32,954
Total Aggregates Business		120,889			86,854			129,636			71,058
Cement		22,468			—			34,697			—
Magnesia Specialties		18,751			20,995			36,541			37,280
Corporate		(25,124	)		(11,608	)		(38,319	)		(27,994	)
Total	$	136,984		$	96,241		$	162,555		$	80,344

10.	Business Segments (continued)

Cement intersegment sales, which are to the ready mixed concrete product line in the West Group, were $20,854,000 and $38,955,000 for the three and six months ended June 30, 2015, respectively.

	June 30,		December 31,		June 30,
	2015		2014		2014
	(Dollars in Thousands)
Assets employed:
Mid-America Group	$	1,343,337	$	1,290,833	$	1,311,860
Southeast Group		601,130		604,044		606,933
West Group		2,559,411		2,444,400		1,084,291
Total Aggregates Business		4,503,878		4,339,277		3,003,084
Cement		2,413,867		2,451,799		—
Magnesia Specialties		148,296		150,359		151,129
Corporate		433,613		522,957		201,830
Total	$	7,499,654	$	7,464,392	$	3,356,043

The assets employed at December 31, 2014 reflect a reclassification of approximately $600 million of goodwill from the Cement segment to the West Group segment compared with the amounts presented in the Segments note (Note O) to the consolidated financial statements in the 2014 Form 10-K. This correction had no impact on the consolidated balance sheet as of December 31, 2014, or the consolidated statements of earnings (including earnings per diluted share), comprehensive earnings, total equity and cash flows for the year then ended. Further, goodwill by reportable segment was correctly presented in the Goodwill and Intangible Assets note (Note B) to the 2014 consolidated financial statements.

10.	Business Segments (continued)

The Aggregates business includes the aggregates product line and aggregates-related downstream product lines, which include asphalt, ready mixed concrete and road paving product lines. All aggregates-related downstream product lines reside in the West Group. The following tables, which are reconciled to consolidated amounts, provide net sales and gross profit by line of business: Aggregates (further divided by product line), Cement and Magnesia Specialties.

	Three Months Ended						Six Months Ended
	June 30,						June 30,
	2015			2014			2015			2014
	(Dollars in Thousands)
Net sales:
Aggregates	$	481,616		$	421,974		$	813,830		$	685,858
Asphalt		18,896			22,627			28,541			33,125
Ready Mixed Concrete		149,750			52,379			277,323			90,388
Road Paving		39,125			43,037			46,249			52,975
Total Aggregates Business		689,387			540,017			1,165,943			862,346
Cement		100,405		—				196,970			—
Magnesia Specialties		60,457			61,920			119,211			119,269
Total	$	850,249		$	601,937		$	1,482,124		$	981,615

Gross profit (loss):
Aggregates	$	137,272		$	100,142		$	178,690		$	110,194
Asphalt		4,314			4,869			2,851			3,443
Ready Mixed Concrete		9,341			6,982			11,424			9,926
Road Paving		3,577			(249	)		265			(4,231	)
Total Aggregates Business		154,504			111,744			193,230			119,332
Cement		30,414			—			49,400			—
Magnesia Specialties		21,224			23,394			41,402			42,149
Corporate		(5,989	)		464			(9,618	)		(43	)
Total	$	200,153		$	135,602		$	274,414		$	161,438

- 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/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=51669610&loc=d3e8981-108599

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 41
-URI http://asc.fasb.org/extlink&oid=51669610&loc=d3e9038-108599

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=51669610&loc=d3e8971-108599

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=51669610&loc=d3e8595-108599

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=51669610&loc=d3e8380-108599

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 32
-URI http://asc.fasb.org/extlink&oid=51669610&loc=d3e8933-108599

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 26
-URI http://asc.fasb.org/extlink&oid=51669610&loc=d3e8844-108599

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 35
-URI http://asc.fasb.org/extlink&oid=51669610&loc=d3e8984-108599

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 40
-URI http://asc.fasb.org/extlink&oid=51669610&loc=d3e9031-108599

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 42
-URI http://asc.fasb.org/extlink&oid=51669610&loc=d3e9054-108599

Reference 11: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=51669610&loc=d3e8538-108599

Reference 12: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 29
-URI http://asc.fasb.org/extlink&oid=51669610&loc=d3e8864-108599

Reference 13: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 31
-URI http://asc.fasb.org/extlink&oid=51669610&loc=d3e8924-108599

Reference 14: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 30
-URI http://asc.fasb.org/extlink&oid=51669610&loc=d3e8906-108599

+ Details

Supplemental Cash Flow Information

6 Months Ended

Jun. 30, 2015

Supplemental Cash Flow Elements [Abstract]

Supplemental Cash Flow Information

11.	Supplemental Cash Flow Information

The components of the change in other assets and liabilities, net, are as follows:

	Six Months Ended
	June 30,
	2015			2014
	(Dollars in Thousands)
Other current and noncurrent assets	$	(5,501	)	$	(6,139	)
Accrued salaries, benefits and payroll taxes		(13,794	)		(755	)
Accrued insurance and other taxes		(1,278	)		3,911
Accrued income taxes		(19,902	)		16,678
Accrued pension, postretirement and postemployment benefits		16,283			4,281
Other current and noncurrent liabilities		(4,878	)		(389	)
	$	(29,070	)	$	17,587

The change in accrued salaries, benefits and payroll taxes in 2015 is primarily attributable to payments of severance expense. The change in accrued income taxes in 2015 is due to the planned utilization of net operating losses acquired with TXI. This resulted in a reclass between current income taxes payable and deferred tax assets.

Noncash investing and financing activities are as follows:

	Six Months Ended
	June 30,
	2015		2014
	(Dollars in Thousands)
Noncash investing and financing activities:
Acquisition of assets through capital lease	$	1,331	$	6,333
Acquisition of assets through asset exchange	$	5,000	$	—

Significant Accounting Policies (Policies)

6 Months Ended

Jun. 30, 2015

Accounting Policies [Abstract]

Organization

The Corporation currently conducts the Aggregates business through three reportable segments: the Mid-America Group, the Southeast Group and the West Group.

AGGREGATES BUSINESS

Reportable Segments

Mid-America Group

Southeast Group

West Group

Operating Locations

Indiana, Iowa,

northern Kansas, Kentucky, Maryland, Minnesota, Missouri,

eastern Nebraska, North Carolina, Ohio,

South Carolina,

Virginia, Washington and

West Virginia

Alabama, Florida, Georgia, Mississippi, Tennessee, Nova Scotia and the Bahamas

Arkansas, Colorado, southern Kansas,

Louisiana, western Nebraska, Nevada, Oklahoma, Texas, Utah

and Wyoming

Basis of Presentation

Revenue Recognition Standard

Consolidated Comprehensive Earnings/Loss and Accumulated Other Comprehensive Loss

Comprehensive earnings attributable to Martin Marietta is as follows:

	Three Months Ended					Six Months Ended
	June 30,					June 30,
	2015			2014		2015			2014
	(Dollars in Thousands)
Net earnings attributable to Martin Marietta Materials, Inc.	$	81,938		$	59,521	$	88,065		$	37,904
Other comprehensive (loss) earnings, net of tax		(6,091	)		603		(6,655	)		1,973
Comprehensive earnings attributable to Martin Marietta Materials, Inc.	$	75,847		$	60,124	$	81,410		$	39,877

1.	Significant Accounting Policies (continued)

Consolidated Comprehensive Earnings/Loss and Accumulated Other Comprehensive Loss (continued)

	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2015		2014		2015		2014
	(Dollars in Thousands)
Net earnings (loss) attributable to noncontrolling interests	$	41	$	103	$	73	$	(1,432	)
Other comprehensive earnings, net of tax		2		1		5		2
Comprehensive earnings (loss) attributable to noncontrolling interests	$	43	$	104	$	78	$	(1,430	)

Changes in accumulated other comprehensive loss, net of tax, are as follows:

	(Dollars in Thousands)
						Unamortized
						Value of
						Terminated			Accumulated
	Pension and					Forward Starting			Other
	Postretirement			Foreign		Interest Rate			Comprehensive
	Benefit Plans			Currency		Swap			Loss
	Three Months Ended June 30, 2015
Balance at beginning of period	$	(105,151	)	$	990	$	(2,562	)	$	(106,723	)
Other comprehensive (loss) earnings before reclassifications, net of tax		(10,670	)		229		—			(10,441	)
Amounts reclassified from accumulated other comprehensive loss, net of tax		4,158			—		192			4,350
Other comprehensive (loss) earnings, net of tax		(6,512	)		229		192			(6,091	)
Balance at end of period	$	(111,663	)	$	1,219	$	(2,370	)	$	(112,814	)

	Three Months Ended June 30, 2014
Balance at beginning of period	$	(44,267	)	$	4,816	$	(3,293	)	$	(42,744	)
Other comprehensive (loss) earnings before reclassifications, net of tax		(426	)		842		—			416
Amounts reclassified from accumulated other comprehensive earnings, net of tax		8			—		179			187
Other comprehensive (loss) earnings, net of tax		(418	)		842		179			603
Balance at end of period	$	(44,685	)	$	5,658	$	(3,114	)	$	(42,141	)

1.	Significant Accounting Policies (continued)

Consolidated Comprehensive Earnings/Loss and Accumulated Other Comprehensive Loss (continued)

	(Dollars in Thousands)
							Unamortized
							Value of
							Terminated			Accumulated
	Pension and						Forward Starting			Other
	Postretirement			Foreign			Interest Rate			Comprehensive
	Benefit Plans			Currency			Swap			Loss
	Six Months Ended June 30, 2015
Balance at beginning of period	$	(106,688	)	$	3,278		$	(2,749	)	$	(106,159	)
Other comprehensive loss before reclassifications, net of tax		(10,845	)		(2,059	)		—			(12,904	)
Amounts reclassified from accumulated other comprehensive (loss) earnings, net of tax		5,870			—			379			6,249
Other comprehensive (loss) earnings, net of tax		(4,975	)		(2,059	)		379			(6,655	)
Balance at end of period	$	(111,663	)	$	1,219		$	(2,370	)	$	(112,814	)

	Six Months Ended June 30, 2014
Balance at beginning of period	$	(44,549	)	$	3,902		$	(3,467	)	$	(44,114	)
Other comprehensive (loss) earnings before reclassifications, net of tax		(430	)		1,756			—			1,326
Amounts reclassified from accumulated other comprehensive earnings, net of tax		294			—			353			647
Other comprehensive (loss) earnings, net of tax		(136	)		1,756			353			1,973
Balance at end of period	$	(44,685	)	$	5,658		$	(3,114	)	$	(42,141	)

1.	Significant Accounting Policies (continued)

Consolidated Comprehensive Earnings/Loss and Accumulated Other Comprehensive Loss (continued)

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

	(Dollars in Thousands)
	Pension and Postretirement Benefit Plans		Unamortized Value of Terminated Forward Starting Interest Rate Swap			Net Noncurrent Deferred Tax Assets

	Three Months Ended June 30, 2015
Balance at beginning of period	$	67,552	$	1,679		$	69,231
Tax effect of other comprehensive earnings		4,073		(125	)		3,948
Balance at end of period	$	71,625	$	1,554		$	73,179

	Three Months Ended June 30, 2014
Balance at beginning of period	$	29,016	$	2,155		$	31,171
Tax effect of other comprehensive earnings		271		(116	)		155
Balance at end of period	$	29,287	$	2,039		$	31,326

	Six Months Ended June 30, 2015
Balance at beginning of period	$	68,568	$	1,799		$	70,367
Tax effect of other comprehensive earnings		3,057		(245	)		2,812
Balance at end of period	$	71,625	$	1,554		$	73,179

	Six Months Ended June 30, 2014
Balance at beginning of period	$	29,198	$	2,269		$	31,467
Tax effect of other comprehensive earnings		89		(230	)		(141	)
Balance at end of period	$	29,287	$	2,039		$	31,326

1.	Significant Accounting Policies (continued)

Consolidated Comprehensive Earnings/Loss and Accumulated Other Comprehensive Loss (continued)

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 and
	2015			2014			2015			2014			comprehensive earnings
	(Dollars in Thousands)
Pension and postretirement benefit plans
Amortization of:
Prior service credit	$	(469	)	$	(791	)	$	(939	)	$	(1,404	)
Actuarial loss		7,274			804			10,546			1,889
		6,805			13			9,607			485		Cost of sales; Selling, general and administrative expenses
Tax benefit		(2,647	)		(5	)		(3,737	)		(191	)	Income tax benefit
	$	4,158		$	8		$	5,870		$	294

Unamortized value of terminated forward starting interest rate swap
Additional interest expense	$	317		$	295		$	624		$	583		Interest expense
Tax benefit		(125	)		(116	)		(245	)		(230	)	Income tax benefit
	$	192		$	179		$	379		$	353

Earnings (Loss) per Common Share

Earnings per Common Share

1.	Significant Accounting Policies (continued)

Earnings per Common Share (continued)

The following table reconciles the numerator and denominator for basic and diluted earnings per common share:

	Three Months Ended						Six Months Ended
	June 30,						June 30,
	2015			2014			2015		2014
	(In Thousands)
Net earnings from continuing operations attributable to Martin Marietta Materials, Inc.	$	81,938		$	59,577		$	88,065	$	37,974
Less: Distributed and undistributed earnings attributable to unvested awards		(876	)		246			403		154
Basic and diluted net earnings available to common shareholders from continuing operations attributable to Martin Marietta Materials, Inc.		82,814			59,331			87,662		37,820
Basic and diluted net loss available to common shareholders from discontinued operations		—			(56	)		—		(70	)
Basic and diluted net earnings available to common shareholders attributable to Martin Marietta Materials, Inc.	$	82,814		$	59,275		$	87,662	$	37,750

Basic weighted-average common shares outstanding		67,373			46,395			67,392		46,355
Effect of dilutive employee and director awards		260			134			262		122
Diluted weighted-average common shares outstanding		67,633			46,529			67,654		46,477

Significant Accounting Policies (Tables)

6 Months Ended

Jun. 30, 2015

Significant Accounting Policies [Line Items]

Changes in Accumulated Other Comprehensive Earnings, Net of Tax

Changes in accumulated other comprehensive loss, net of tax, are as follows:

	(Dollars in Thousands)
						Unamortized
						Value of
						Terminated			Accumulated
	Pension and					Forward Starting			Other
	Postretirement			Foreign		Interest Rate			Comprehensive
	Benefit Plans			Currency		Swap			Loss
	Three Months Ended June 30, 2015
Balance at beginning of period	$	(105,151	)	$	990	$	(2,562	)	$	(106,723	)
Other comprehensive (loss) earnings before reclassifications, net of tax		(10,670	)		229		—			(10,441	)
Amounts reclassified from accumulated other comprehensive loss, net of tax		4,158			—		192			4,350
Other comprehensive (loss) earnings, net of tax		(6,512	)		229		192			(6,091	)
Balance at end of period	$	(111,663	)	$	1,219	$	(2,370	)	$	(112,814	)

	Three Months Ended June 30, 2014
Balance at beginning of period	$	(44,267	)	$	4,816	$	(3,293	)	$	(42,744	)
Other comprehensive (loss) earnings before reclassifications, net of tax		(426	)		842		—			416
Amounts reclassified from accumulated other comprehensive earnings, net of tax		8			—		179			187
Other comprehensive (loss) earnings, net of tax		(418	)		842		179			603
Balance at end of period	$	(44,685	)	$	5,658	$	(3,114	)	$	(42,141	)

	(Dollars in Thousands)
							Unamortized
							Value of
							Terminated			Accumulated
	Pension and						Forward Starting			Other
	Postretirement			Foreign			Interest Rate			Comprehensive
	Benefit Plans			Currency			Swap			Loss
	Six Months Ended June 30, 2015
Balance at beginning of period	$	(106,688	)	$	3,278		$	(2,749	)	$	(106,159	)
Other comprehensive loss before reclassifications, net of tax		(10,845	)		(2,059	)		—			(12,904	)
Amounts reclassified from accumulated other comprehensive (loss) earnings, net of tax		5,870			—			379			6,249
Other comprehensive (loss) earnings, net of tax		(4,975	)		(2,059	)		379			(6,655	)
Balance at end of period	$	(111,663	)	$	1,219		$	(2,370	)	$	(112,814	)

	Six Months Ended June 30, 2014
Balance at beginning of period	$	(44,549	)	$	3,902		$	(3,467	)	$	(44,114	)
Other comprehensive (loss) earnings before reclassifications, net of tax		(430	)		1,756			—			1,326
Amounts reclassified from accumulated other comprehensive earnings, net of tax		294			—			353			647
Other comprehensive (loss) earnings, net of tax		(136	)		1,756			353			1,973
Balance at end of period	$	(44,685	)	$	5,658		$	(3,114	)	$	(42,141	)

Noncurrent Deferred Tax Assets Recorded In Accumulated Other Comprehensive Loss

1.	Significant Accounting Policies (continued)

Consolidated Comprehensive Earnings/Loss and Accumulated Other Comprehensive Loss (continued)

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

	(Dollars in Thousands)
	Pension and Postretirement Benefit Plans		Unamortized Value of Terminated Forward Starting Interest Rate Swap			Net Noncurrent Deferred Tax Assets

	Three Months Ended June 30, 2015
Balance at beginning of period	$	67,552	$	1,679		$	69,231
Tax effect of other comprehensive earnings		4,073		(125	)		3,948
Balance at end of period	$	71,625	$	1,554		$	73,179

	Three Months Ended June 30, 2014
Balance at beginning of period	$	29,016	$	2,155		$	31,171
Tax effect of other comprehensive earnings		271		(116	)		155
Balance at end of period	$	29,287	$	2,039		$	31,326

	Six Months Ended June 30, 2015
Balance at beginning of period	$	68,568	$	1,799		$	70,367
Tax effect of other comprehensive earnings		3,057		(245	)		2,812
Balance at end of period	$	71,625	$	1,554		$	73,179

	Six Months Ended June 30, 2014
Balance at beginning of period	$	29,198	$	2,269		$	31,467
Tax effect of other comprehensive earnings		89		(230	)		(141	)
Balance at end of period	$	29,287	$	2,039		$	31,326

Reclassification Out of Accumulated Other Comprehensive Loss

1.	Significant Accounting Policies (continued)

Consolidated Comprehensive Earnings/Loss and Accumulated Other Comprehensive Loss (continued)

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 and
	2015			2014			2015			2014			comprehensive earnings
	(Dollars in Thousands)
Pension and postretirement benefit plans
Amortization of:
Prior service credit	$	(469	)	$	(791	)	$	(939	)	$	(1,404	)
Actuarial loss		7,274			804			10,546			1,889
		6,805			13			9,607			485		Cost of sales; Selling, general and administrative expenses
Tax benefit		(2,647	)		(5	)		(3,737	)		(191	)	Income tax benefit
	$	4,158		$	8		$	5,870		$	294

Unamortized value of terminated forward starting interest rate swap
Additional interest expense	$	317		$	295		$	624		$	583		Interest expense
Tax benefit		(125	)		(116	)		(245	)		(230	)	Income tax benefit
	$	192		$	179		$	379		$	353

Basic and Diluted Earnings (Loss) per Common Share

1.	Significant Accounting Policies (continued)

Earnings per Common Share (continued)

The following table reconciles the numerator and denominator for basic and diluted earnings per common share:

	Three Months Ended						Six Months Ended
	June 30,						June 30,
	2015			2014			2015		2014
	(In Thousands)
Net earnings from continuing operations attributable to Martin Marietta Materials, Inc.	$	81,938		$	59,577		$	88,065	$	37,974
Less: Distributed and undistributed earnings attributable to unvested awards		(876	)		246			403		154
Basic and diluted net earnings available to common shareholders from continuing operations attributable to Martin Marietta Materials, Inc.		82,814			59,331			87,662		37,820
Basic and diluted net loss available to common shareholders from discontinued operations		—			(56	)		—		(70	)
Basic and diluted net earnings available to common shareholders attributable to Martin Marietta Materials, Inc.	$	82,814		$	59,275		$	87,662	$	37,750

Basic weighted-average common shares outstanding		67,373			46,395			67,392		46,355
Effect of dilutive employee and director awards		260			134			262		122
Diluted weighted-average common shares outstanding		67,633			46,529			67,654		46,477

Parent

Significant Accounting Policies [Line Items]

Comprehensive Earnings (Loss)

Comprehensive earnings attributable to Martin Marietta is as follows:

	Three Months Ended					Six Months Ended
	June 30,					June 30,
	2015			2014		2015			2014
	(Dollars in Thousands)
Net earnings attributable to Martin Marietta Materials, Inc.	$	81,938		$	59,521	$	88,065		$	37,904
Other comprehensive (loss) earnings, net of tax		(6,091	)		603		(6,655	)		1,973
Comprehensive earnings attributable to Martin Marietta Materials, Inc.	$	75,847		$	60,124	$	81,410		$	39,877

Noncontrolling Interests

Significant Accounting Policies [Line Items]

Comprehensive Earnings (Loss)

	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2015		2014		2015		2014
	(Dollars in Thousands)
Net earnings (loss) attributable to noncontrolling interests	$	41	$	103	$	73	$	(1,432	)
Other comprehensive earnings, net of tax		2		1		5		2
Comprehensive earnings (loss) attributable to noncontrolling interests	$	43	$	104	$	78	$	(1,430	)

Business Combinations and Assets Held for Sale (Tables)

6 Months Ended

Jun. 30, 2015

Business Combinations [Abstract]

Pro Forma Financial Information

The pro forma financial information presented below is for informational purposes only and is not indicative of the results of operations that would have been achieved if the acquisitions had taken place as of January 1, 2014.

	Three Months Ended		Six Months Ended
	June 30, 2014		June 30, 2014
	(Dollars in Thousands)
Net sales	$	831,760	$	1,395,150
Earnings (Loss) from continuing operations attributable to controlling interest	$	68,313	$	(11,474	)

Goodwill (Tables)

6 Months Ended

Jun. 30, 2015

Goodwill And Intangible Assets Disclosure [Abstract]

Changes in Goodwill

The following table shows the changes in goodwill by reportable segment and in total:

	(Dollars in Thousands)
	Mid-America			Southeast		West
	Group			Group		Group		Cement			Total
	Six Months Ended June 30, 2015
Balance at January 1, 2015	$	282,117		$	50,346	$	852,436	$	883,900		$	2,068,799
Adjustments to purchase price allocations		—			—		15,882		(18,978	)		(3,096	)
Acquisitions		—			—		893		—			893
Divestitures		(714	)		—		—		—			(714	)
Balance at June 30, 2015	$	281,403		$	50,346	$	869,211	$	864,922		$	2,065,882

Inventories, Net (Tables)

6 Months Ended

Jun. 30, 2015

Inventory Disclosure [Abstract]

Schedule of Inventories Net

	June 30,			December 31,			June 30,
	2015			2014			2014
	(Dollars in Thousands)
Finished products	$	427,298		$	413,766		$	358,759
Products in process and raw materials		60,498			65,250			20,732
Supplies and expendable parts		112,587			125,092			65,287
		600,383			604,108			444,778
Less: Allowances		(120,527	)		(119,189	)		(96,610	)
Total	$	479,856		$	484,919		$	348,168

Long-Term Debt (Tables)

6 Months Ended

Jun. 30, 2015

Debt Disclosure [Abstract]

Long-Term Debt

	June 30,			December 31,			June 30,
	2015			2014			2014
	(Dollars in Thousands)
6.6% Senior Notes, due 2018	$	299,243		$	299,123		$	299,006
7% Debentures, due 2025		124,516			124,500			124,485
6.25% Senior Notes, due 2037		228,208			228,184			228,165
4.25 % Senior Notes, due 2024		395,511			395,309			—
Floating Rate Notes, due 2017, interest rate of 1.38% and 1.33% at June 30, 2015 and December 31, 2014, respectively		299,108			298,869			—
Term Loan Facility, due 2018, interest rate of 1.69% at June 30, 2015; 1.67% at December 31, 2014; and 1.65% at June 30, 2014		230,167			236,258			242,350
Revolving Facility, interest rate of 1.40% at June 30, 2014		—			—			40,000
Trade Receivable Facility, interest rate of 0.88% and 0.75% at June 30, 3015 and 2014, respectively		80,000			—			150,000
Other notes		1,248			3,152			795
Total debt		1,658,001			1,585,395			1,084,801
Less: Current maturities		(15,966	)		(14,336	)		(12,404	)
Long-term debt	$	1,642,035		$	1,571,059		$	1,072,397

- 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/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(e),(f))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21538-112644

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21506-112644

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28541-108399

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21521-112644

+ Details

Income Taxes (Tables)

6 Months Ended

Jun. 30, 2015

Income Tax Disclosure [Abstract]

Schedule of Estimated Effective Income Tax Rate

	Six Months Ended June 30,
	2015			2014
Estimated effective income tax rate:
Continuing operations		30.2	%		29.8	%
Discontinued operations		—			26.4	%
Consolidated overall		30.2	%		29.8	%

Pension and Postretirement Benefits (Tables)

6 Months Ended

Jun. 30, 2015

Compensation And Retirement Disclosure [Abstract]

Schedule of Components of Net Periodic Benefit Cost

The estimated components of the recorded net periodic benefit cost (credit) for pension and postretirement benefits are as follows:

	Three Months Ended June 30,
	Pension						Postretirement Benefits
	2015			2014			2015			2014
	(Dollars in Thousands)
Service cost	$	5,513		$	3,092		$	34		$	51
Interest cost		8,213			5,624			229			305
Expected return on assets		(8,887	)		(6,677	)		—			—
Amortization of:
Prior service cost (credit)		101			96			(570	)		(887	)
Actuarial loss (gain)		7,351			877			(77	)		(73	)
Special termination benefit		1,206			—			—			—
Net periodic benefit cost (credit)	$	13,497		$	3,012		$	(384	)	$	(604	)

	Six Months Ended June 30,
	Pension						Postretirement Benefits
	2015			2014			2015			2014
	(Dollars in Thousands)
Service cost	$	11,505		$	7,131		$	68		$	93
Interest cost		16,575			12,971			464			559
Expected return on assets		(18,190	)		(15,400	)		—			—
Amortization of:
Prior service cost (credit)		211			223			(1,150	)		(1,627	)
Actuarial loss (gain)		10,700			2,022			(154	)		(133	)
Special termination benefit		1,462			—			—			—
Net periodic benefit cost (credit)	$	22,263		$	6,947		$	(772	)	$	(1,108	)

Business Segments (Tables)

6 Months Ended

Jun. 30, 2015

Segment Reporting [Abstract]

Financial Data for Continuing Operation For Corporation's Reportable Business Segments

10.	Business Segments (Continued)

	Three Months Ended						Six Months Ended
	June 30,						June 30,
	2015			2014			2015			2014
	(Dollars in Thousands)
Total revenues:
Mid-America Group	$	257,649		$	240,526		$	398,482		$	356,235
Southeast Group		81,518			75,168			146,195			134,988
West Group		411,235			286,811			731,807			477,598
Total Aggregates Business		750,402			602,505			1,276,484			968,821
Cement		105,899			—			207,999			—
Magnesia Specialties		65,118			66,720			128,282			129,034
Total	$	921,419		$	669,225		$	1,612,765		$	1,097,855

Net sales:
Mid-America Group	$	237,415		$	218,703		$	367,120		$	325,236
Southeast Group		76,483			70,725			136,253			126,106
West Group		375,489			250,589			662,570			411,004
Total Aggregates Business		689,387			540,017			1,165,943			862,346
Cement		100,405			—			196,970			—
Magnesia Specialties		60,457			61,920			119,211			119,269
Total	$	850,249		$	601,937		$	1,482,124		$	981,615

Earnings (Loss) from operations:
Mid-America Group	$	66,894		$	57,283		$	62,691		$	45,517
Southeast Group		4,818			(1,302	)		3,269			(7,413	)
West Group		49,177			30,873			63,676			32,954
Total Aggregates Business		120,889			86,854			129,636			71,058
Cement		22,468			—			34,697			—
Magnesia Specialties		18,751			20,995			36,541			37,280
Corporate		(25,124	)		(11,608	)		(38,319	)		(27,994	)
Total	$	136,984		$	96,241		$	162,555		$	80,344

Asset Employed for Continuing Operations for Corporations Reportable Business Segments

	June 30,		December 31,		June 30,
	2015		2014		2014
	(Dollars in Thousands)
Assets employed:
Mid-America Group	$	1,343,337	$	1,290,833	$	1,311,860
Southeast Group		601,130		604,044		606,933
West Group		2,559,411		2,444,400		1,084,291
Total Aggregates Business		4,503,878		4,339,277		3,003,084
Cement		2,413,867		2,451,799		—
Magnesia Specialties		148,296		150,359		151,129
Corporate		433,613		522,957		201,830
Total	$	7,499,654	$	7,464,392	$	3,356,043

Net Sales and Gross Profit by Line of Business

	Three Months Ended						Six Months Ended
	June 30,						June 30,
	2015			2014			2015			2014
	(Dollars in Thousands)
Net sales:
Aggregates	$	481,616		$	421,974		$	813,830		$	685,858
Asphalt		18,896			22,627			28,541			33,125
Ready Mixed Concrete		149,750			52,379			277,323			90,388
Road Paving		39,125			43,037			46,249			52,975
Total Aggregates Business		689,387			540,017			1,165,943			862,346
Cement		100,405		—				196,970			—
Magnesia Specialties		60,457			61,920			119,211			119,269
Total	$	850,249		$	601,937		$	1,482,124		$	981,615

Gross profit (loss):
Aggregates	$	137,272		$	100,142		$	178,690		$	110,194
Asphalt		4,314			4,869			2,851			3,443
Ready Mixed Concrete		9,341			6,982			11,424			9,926
Road Paving		3,577			(249	)		265			(4,231	)
Total Aggregates Business		154,504			111,744			193,230			119,332
Cement		30,414			—			49,400			—
Magnesia Specialties		21,224			23,394			41,402			42,149
Corporate		(5,989	)		464			(9,618	)		(43	)
Total	$	200,153		$	135,602		$	274,414		$	161,438

Supplemental Cash Flow Information (Tables)

6 Months Ended

Jun. 30, 2015

Supplemental Cash Flow Elements [Abstract]

Components of Change in Other Assets and Liabilities, Net

The components of the change in other assets and liabilities, net, are as follows:

	Six Months Ended
	June 30,
	2015			2014
	(Dollars in Thousands)
Other current and noncurrent assets	$	(5,501	)	$	(6,139	)
Accrued salaries, benefits and payroll taxes		(13,794	)		(755	)
Accrued insurance and other taxes		(1,278	)		3,911
Accrued income taxes		(19,902	)		16,678
Accrued pension, postretirement and postemployment benefits		16,283			4,281
Other current and noncurrent liabilities		(4,878	)		(389	)
	$	(29,070	)	$	17,587

Schedule of Noncash Investing and Financing Activities

Noncash investing and financing activities are as follows:

	Six Months Ended
	June 30,
	2015		2014
	(Dollars in Thousands)
Noncash investing and financing activities:
Acquisition of assets through capital lease	$	1,331	$	6,333
Acquisition of assets through asset exchange	$	5,000	$	—

Significant Accounting Policies - Additional Information (Detail) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2015 USD ($) State	Jun. 30, 2014 USD ($)	Jun. 30, 2015 USD ($) Facility State Segment	Jun. 30, 2014 USD ($)	Dec. 31, 2014
Significant Accounting Policies [Line Items]
Number of quarries distribution facilities and plants \| Facility			400
Number of states with aggregates business sales by destination \| State	32		32
Number of reportable segments \| Segment			3
Other comprehensive loss before reclassifications for pension and postretirement benefit plans, tax benefit \| $	$ 6,793	$ 276	$ 6,904	$ 280
Aggregates Product Line \| Product Concentration Risk \| Sales
Significant Accounting Policies [Line Items]
Total net sales, percentage					58.00%
Aggregates-Related Downstream Product Lines \| Product Concentration Risk \| Sales
Significant Accounting Policies [Line Items]
Total net sales, percentage					25.00%
Cement \| Product Concentration Risk \| Sales
Significant Accounting Policies [Line Items]
Total net sales, percentage					8.00%
Magnesia Specialties \| Product Concentration Risk \| Sales
Significant Accounting Policies [Line Items]
Total net sales, percentage					9.00%

Comprehensive Earnings Attributable to Martin Marietta Materials Incorporated (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Statement Of Income And Comprehensive Income [Abstract]
Net earnings attributable to Martin Marietta Materials, Inc.	$ 81,938	$ 59,521	$ 88,065	$ 37,904
Other comprehensive (loss) earnings, net of tax	(6,091)	603	(6,655)	1,973
Earnings attributable to Martin Marietta Materials, Inc.	$ 75,847	$ 60,124	$ 81,410	$ 39,877

- Definition

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

+ References + Details

Comprehensive Earnings (Loss) Attributable to Noncontrolling Interests (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Statement Of Income And Comprehensive Income [Abstract]
Net earnings (loss) attributable to noncontrolling interests	$ 41	$ 103	$ 73	$ (1,432)
Other comprehensive earnings, net of tax	2	1	5	2
Comprehensive earnings (loss) attributable to noncontrolling interests	$ 43	$ 104	$ 78	$ (1,430)

Changes in Accumulated Other Comprehensive Earnings, Net of Tax (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	$ (106,723)	$ (42,744)	$ (106,159)	$ (44,114)
Other comprehensive (loss) earnings before reclassifications, net of tax	(10,441)	416	(12,904)	1,326
Amounts reclassified from accumulated other comprehensive loss, net of tax	4,350	187	6,249	647
Other comprehensive (loss) earnings, net of tax	(6,091)	603	(6,655)	1,973
Balance at end of period	(112,814)	(42,141)	(112,814)	(42,141)
Pension and Postretirement Benefit Plans
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(105,151)	(44,267)	(106,688)	(44,549)
Other comprehensive (loss) earnings before reclassifications, net of tax	(10,670)	(426)	(10,845)	(430)
Amounts reclassified from accumulated other comprehensive loss, net of tax	4,158	8	5,870	294
Other comprehensive (loss) earnings, net of tax	(6,512)	(418)	(4,975)	(136)
Balance at end of period	(111,663)	(44,685)	(111,663)	(44,685)
Foreign Currency
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	990	4,816	3,278	3,902
Other comprehensive (loss) earnings before reclassifications, net of tax	229	842	(2,059)	1,756
Other comprehensive (loss) earnings, net of tax	229	842	(2,059)	1,756
Balance at end of period	1,219	5,658	1,219	5,658
Unamortized Value of Terminated Forward Starting Interest Rate Swap
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(2,562)	(3,293)	(2,749)	(3,467)
Amounts reclassified from accumulated other comprehensive loss, net of tax	192	179	379	353
Other comprehensive (loss) earnings, net of tax	192	179	379	353
Balance at end of period	$ (2,370)	$ (3,114)	$ (2,370)	$ (3,114)

- Definition

Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

+ References + Details

Noncurrent Deferred Tax Assets Recorded in Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Equity [Abstract]
Balance at beginning of period, Pension and Postretirement Benefit Plans	$ 67,552	$ 29,016	$ 68,568	$ 29,198
Other comprehensive earnings, tax effect, Pension and Postretirement Benefit Plans	4,073	271	3,057	89
Balance at end of period, Pension and Postretirement Benefit Plans	71,625	29,287	71,625	29,287
Balance at beginning of period, Unamortized Value of Terminated Forward Starting Interest Rate Swap	1,679	2,155	1,799	2,269
Other comprehensive earnings, tax effect, Unamortized Value of Terminated Forward Starting Interest Rate Swap	(125)	(116)	(245)	(230)
Balance at end of period, Unamortized Value of Terminated Forward Starting Interest Rate Swap	1,554	2,039	1,554	2,039
Balance at beginning of period, Net Non current Deferred Tax Assets	69,231	31,171	70,367	31,467
Other comprehensive earnings, tax effect, Net Non current Deferred Tax Assets	3,948	155	2,812	(141)
Balance at end of period, Net Non current Deferred Tax Assets	$ 73,179	$ 31,326	$ 73,179	$ 31,326

Reclassifications Out of Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest expense	$ 19,087	$ 12,947	$ 38,418	$ 25,149
Income tax benefit	38,929	23,906	38,117	15,482
Earnings from Continuing Operations	81,979	59,680	88,138	36,542
Reclassification out of Accumulated Other Comprehensive Income \| Pension and Postretirement Benefit Plans
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Prior service credit	(469)	(791)	(939)	(1,404)
Actuarial loss	7,274	804	10,546	1,889
Income tax benefit	(2,647)	(5)	(3,737)	(191)
Earnings from Continuing Operations	4,158	8	5,870	294
Reclassification out of Accumulated Other Comprehensive Income \| Pension and Postretirement Benefit Plans \| Cost of sale; Selling, General & Administrative Expenses
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total reclassifications out of accumulated other comprehensive loss before taxes	6,805	13	9,607	485
Reclassification out of Accumulated Other Comprehensive Income \| Unamortized Value of Terminated Forward Starting Interest Rate Swap
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest expense	317	295	624	583
Income tax benefit	(125)	(116)	(245)	(230)
Earnings from Continuing Operations	$ 192	$ 179	$ 379	$ 353

Basic and Diluted Earnings (Loss) Per Common Share (Detail) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Earnings Per Share [Abstract]
Net earnings from continuing operations attributable to Martin Marietta Materials, Inc.	$ 81,938	$ 59,577	$ 88,065	$ 37,974
Less: Distributed and undistributed earnings attributable to unvested awards	876	(246)	(403)	(154)
Basic and diluted net earnings available to common shareholders from continuing operations attributable to Martin Marietta Materials, Inc.	82,814	59,331	87,662	37,820
Basic and diluted net loss available to common shareholders from discontinued operations		(56)		(70)
Basic and diluted net earnings available to common shareholders attributable to Martin Marietta Materials, Inc.	$ 82,814	$ 59,275	$ 87,662	$ 37,750
Basic weighted-average common shares outstanding	67,373	46,395	67,392	46,355
Effect of dilutive employee and director awards	260	134	262	122
Diluted weighted-average common shares outstanding	67,633	46,529	67,654	46,477

- 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

Business Combinations and Assets Held for Sale - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Business Combinations And Assets Held For Sale [Line Items]
Acquisition-related expenses, net	$ 2,092	$ 5,280	$ 3,696	$ 15,060
Texas Industries Inc.
Business Combinations And Assets Held For Sale [Line Items]
Acquisition date			Jul. 01, 2014
Total revenues from operations included in the consolidated statement of earnings	243,837		$ 467,896
Total earnings from operations included in the consolidated statement of earnings	25,242		33,936
Acquisition-related expenses, net	$ 2,135	$ 5,265	$ 3,586	$ 14,991

Pro Forma Financial Information (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2014	Jun. 30, 2014
Business Combinations [Abstract]
Net sales	$ 831,760	$ 1,395,150
Earnings (Loss) from continuing operations attributable to controlling interest	$ 68,313	$ (11,474)

Changes in Goodwill (Detail) $ in Thousands	6 Months Ended
Changes in Goodwill (Detail) $ in Thousands	Jun. 30, 2015 USD ($)
Goodwill [Line Items]
Balance at beginning of period	$ 2,068,799
Adjustments to purchase price allocations	(3,096)
Acquisitions	893
Divestitures	(714)
Balance at end of period	2,065,882
Mid-America Group
Goodwill [Line Items]
Balance at beginning of period	282,117
Divestitures	(714)
Balance at end of period	281,403
Southeast Group
Goodwill [Line Items]
Balance at beginning of period	50,346
Balance at end of period	50,346
West Group
Goodwill [Line Items]
Balance at beginning of period	852,436
Adjustments to purchase price allocations	15,882
Acquisitions	893
Balance at end of period	869,211
Cement
Goodwill [Line Items]
Balance at beginning of period	883,900
Adjustments to purchase price allocations	(18,978)
Balance at end of period	$ 864,922

Inventories Net (Detail) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2014
Inventory Disclosure [Abstract]
Finished products	$ 427,298	$ 413,766	$ 358,759
Products in process and raw materials	60,498	65,250	20,732
Supplies and expendable parts	112,587	125,092	65,287
Inventories, Gross	600,383	604,108	444,778
Less: Allowances	(120,527)	(119,189)	(96,610)
Total	$ 479,856	$ 484,919	$ 348,168

Long Term Debt (Detail) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2014
Debt Instrument [Line Items]
Total debt	$ 1,658,001	$ 1,585,395	$ 1,084,801
Less: Current maturities	(15,966)	(14,336)	(12,404)
Long-term debt	1,642,035	1,571,059	1,072,397
6.6% Senior Notes, Due 2018
Debt Instrument [Line Items]
Total debt	299,243	299,123	299,006
7% Debentures, Due 2025
Debt Instrument [Line Items]
Total debt	124,516	124,500	124,485
6.25% Senior Notes, Due 2037
Debt Instrument [Line Items]
Total debt	228,208	228,184	228,165
4.25% Senior Notes, Due 2024
Debt Instrument [Line Items]
Total debt	395,511	395,309
Floating Rate Notes, Due 2017
Debt Instrument [Line Items]
Total debt	299,108	298,869
Term Loan Facility, Due 2018
Debt Instrument [Line Items]
Total debt	230,167	236,258	242,350
Revolving Facility
Debt Instrument [Line Items]
Total debt			40,000
Trade Receivable Facility
Debt Instrument [Line Items]
Total debt	80,000		150,000
Other Notes
Debt Instrument [Line Items]
Total debt	$ 1,248	$ 3,152	$ 795

Long Term Debt (Parenthetical) (Detail)	6 Months Ended
Long Term Debt (Parenthetical) (Detail)	Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2014
6.6% Senior Notes, Due 2018
Debt Instrument [Line Items]
Maturity date	2018
Interest rate on notes	6.60%
7% Debentures, Due 2025
Debt Instrument [Line Items]
Maturity date	2025
Interest rate on notes	7.00%
6.25% Senior Notes, Due 2037
Debt Instrument [Line Items]
Maturity date	2037
Interest rate on notes	6.25%
4.25% Senior Notes, Due 2024
Debt Instrument [Line Items]
Maturity date	2024
Interest rate on notes	4.25%
Floating Rate Notes, Due 2017
Debt Instrument [Line Items]
Maturity date	2017
Interest rate	1.38%	1.33%
Term Loan Facility, Due 2018
Debt Instrument [Line Items]
Maturity date	2018
Interest rate	1.69%	1.67%	1.65%
Revolving Facility
Debt Instrument [Line Items]
Credit Facility interest rate			1.40%
Trade Receivable Facility
Debt Instrument [Line Items]
Credit Facility interest rate	0.88%		0.75%

Long-Term Debt - Additional information (Detail) - USD ($)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Debt Instrument [Line Items]
Maximum consolidated debt reduction for unrestricted cash and cash equivalents for debt covenant calculation			$ 200,000,000
Additional interest expense	$ 317,000	$ 295,000	624,000	$ 583,000
Maximum \| Texas Industries Inc.
Debt Instrument [Line Items]
Amendment consolidated EBITDA					$ 95,000,000
Acquisition integration expenses					70,000,000
Minimum
Debt Instrument [Line Items]
Reduction of consolidated debt in the debt ratio calculation			$ 50,000,000
Including Acquisition Bridge Debt \| Maximum
Debt Instrument [Line Items]
Debt covenant	3.50		3.50
Excluding Acquisition Bridge Debt \| Maximum
Debt Instrument [Line Items]
Debt covenant	3.75		3.75
Trade Receivable Facility
Debt Instrument [Line Items]
Credit facility commitment	$ 250,000,000		$ 250,000,000
Debt instrument maturity period			Sep. 30, 2016
Eligible trade receivables	450,791,000	311,792,000	$ 450,791,000	311,792,000	369,575,000
Credit facility borrowing base	377,688,000	258,787,000	377,688,000	258,787,000	313,428,000
Term Loan Facility
Debt Instrument [Line Items]
Credit facility commitment	250,000,000		250,000,000
Revolving Facility
Debt Instrument [Line Items]
Credit facility commitment	350,000,000		$ 350,000,000
Senior unsecured revolving facility, maturity period			5 years
Outstanding letters of credit	$ 2,507,000	$ 2,507,000	$ 2,507,000	$ 2,507,000	$ 2,507,000
9.25% Senior Notes due 2020 \| Texas Industries Inc.
Debt Instrument [Line Items]
Interest rate on notes					9.25%
Maturity date					2020
6.6% Senior Notes, Due 2018
Debt Instrument [Line Items]
Interest rate on notes	6.60%		6.60%
Maturity date			2018
Increase in annual interest expense due to ongoing amortization of the terminated value of the swap agreements			$ 1,200,000
London Interbank Offered Rate(LIBOR) \| Trade Receivable Facility
Debt Instrument [Line Items]
Basis spread on variable rate			0.70%

Financial Instruments - Additional Information (Detail) - USD ($)	Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2014
Fair Value Disclosures [Abstract]
Long-term debt, carrying values	$ 1,658,001,000	$ 1,585,395,000	$ 1,084,801,000
Long-term debt, fair values	$ 1,729,511,000	$ 1,680,584,000	$ 1,168,302,000

Schedule of Estimated Effective Income Tax Rate (Detail)	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Income Tax Disclosure [Abstract]
Continuing operations	30.20%	29.80%
Discontinued operations		26.40%
Consolidated overall	30.20%	29.80%

Schedule of Components of Net Periodic Benefit Cost (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Pension
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 5,513	$ 3,092	$ 11,505	$ 7,131
Interest cost	8,213	5,624	16,575	12,971
Expected return on assets	(8,887)	(6,677)	(18,190)	(15,400)
Prior service cost (credit)	101	96	211	223
Actuarial loss (gain)	7,351	877	10,700	2,022
Special termination benefit	1,206		1,462
Net periodic benefit cost (credit)	13,497	3,012	22,263	6,947
Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	34	51	68	93
Interest cost	229	305	464	559
Prior service cost (credit)	(570)	(887)	(1,150)	(1,627)
Actuarial loss (gain)	(77)	(73)	(154)	(133)
Net periodic benefit cost (credit)	$ (384)	$ (604)	$ (772)	$ (1,108)

Commitments and Contingencies - Additional Information (Detail) - USD ($)	6 Months Ended	12 Months Ended
	Jun. 30, 2015	Dec. 31, 2013	Dec. 31, 2014	Jun. 30, 2014
Commitments and Contingencies [Line Items]
Guarantee of affiliate's obligations	$ 25,000,000
Loan to affiliate		$ 3,402,000
Due from affiliate	$ 6,000,000		$ 6,000,000	$ 6,000,000
Percentage of employees represented in labor union	12.00%
Cement
Commitments and Contingencies [Line Items]
Percentage of employees represented in labor union	100.00%
Magnesia Specialties
Commitments and Contingencies [Line Items]
Percentage of employees represented in labor union	100.00%
Loan Due May 2016
Commitments and Contingencies [Line Items]
Due from affiliate			$ 1,808,000	$ 2,455,000

Business Segments - Additional Information (Detail)	3 Months Ended		6 Months Ended		12 Months Ended
Business Segments - Additional Information (Detail)	Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)	Jun. 30, 2015 USD ($) Segment	Jun. 30, 2014 USD ($)	Dec. 31, 2014 USD ($)
Segment Reporting Information [Line Items]
Reportable business segments \| Segment			3
Total revenues	$ (921,419,000)	$ (669,225,000)	$ (1,612,765,000)	$ (1,097,855,000)
Reclassification of goodwill					$ 600,000,000
Intersegment Eliminations
Segment Reporting Information [Line Items]
Total revenues	$ 20,854,000		$ 38,955,000

Financial Data for Continuing Operations for Corporations Reportable Business Segments (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Segment Reporting Information [Line Items]
Total revenues	$ 921,419	$ 669,225	$ 1,612,765	$ 1,097,855
Net Sales	850,249	601,937	1,482,124	981,615
Earnings (Loss) from operations	136,984	96,241	162,555	80,344
Operating Segments \| Mid-America Group
Segment Reporting Information [Line Items]
Total revenues	257,649	240,526	398,482	356,235
Net Sales	237,415	218,703	367,120	325,236
Earnings (Loss) from operations	66,894	57,283	62,691	45,517
Operating Segments \| Southeast Group
Segment Reporting Information [Line Items]
Total revenues	81,518	75,168	146,195	134,988
Net Sales	76,483	70,725	136,253	126,106
Earnings (Loss) from operations	4,818	(1,302)	3,269	(7,413)
Operating Segments \| West Group
Segment Reporting Information [Line Items]
Total revenues	411,235	286,811	731,807	477,598
Net Sales	375,489	250,589	662,570	411,004
Earnings (Loss) from operations	49,177	30,873	63,676	32,954
Operating Segments \| Cement
Segment Reporting Information [Line Items]
Total revenues	105,899		207,999
Net Sales	100,405		196,970
Earnings (Loss) from operations	22,468		34,697
Operating Segments \| Magnesia Specialties
Segment Reporting Information [Line Items]
Total revenues	65,118	66,720	128,282	129,034
Net Sales	60,457	61,920	119,211	119,269
Earnings (Loss) from operations	18,751	20,995	36,541	37,280
Aggregates Business
Segment Reporting Information [Line Items]
Total revenues	750,402	602,505	1,276,484	968,821
Net Sales	689,387	540,017	1,165,943	862,346
Earnings (Loss) from operations	120,889	86,854	129,636	71,058
Corporate
Segment Reporting Information [Line Items]
Earnings (Loss) from operations	$ (25,124)	$ (11,608)	$ (38,319)	$ (27,994)

Asset Employed for Continuing Operations for Corporations Reportable Business Segments (Detail) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2014
Segment Reporting Asset Reconciling Item [Line Items]
Assets employed, Total	$ 7,499,654	$ 7,464,392	$ 3,356,043
Operating Segments \| Mid-America Group
Segment Reporting Asset Reconciling Item [Line Items]
Assets employed, Total	1,343,337	1,290,833	1,311,860
Operating Segments \| Southeast Group
Segment Reporting Asset Reconciling Item [Line Items]
Assets employed, Total	601,130	604,044	606,933
Operating Segments \| West Group
Segment Reporting Asset Reconciling Item [Line Items]
Assets employed, Total	2,559,411	2,444,400	1,084,291
Operating Segments \| Cement
Segment Reporting Asset Reconciling Item [Line Items]
Assets employed, Total	2,413,867	2,451,799
Operating Segments \| Magnesia Specialties
Segment Reporting Asset Reconciling Item [Line Items]
Assets employed, Total	148,296	150,359	151,129
Aggregates Business
Segment Reporting Asset Reconciling Item [Line Items]
Assets employed, Total	4,503,878	4,339,277	3,003,084
Corporate
Segment Reporting Asset Reconciling Item [Line Items]
Assets employed, Total	$ 433,613	$ 522,957	$ 201,830

Net Sales and Gross Profit by Line of Business (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Product Information [Line Items]
Net Sales	$ 850,249	$ 601,937	$ 1,482,124	$ 981,615
Gross profit (loss)	200,153	135,602	274,414	161,438
Aggregates Business
Product Information [Line Items]
Net Sales	689,387	540,017	1,165,943	862,346
Gross profit (loss)	154,504	111,744	193,230	119,332
Operating Segments \| Cement
Product Information [Line Items]
Net Sales	100,405		196,970
Gross profit (loss)	30,414		49,400
Operating Segments \| Magnesia Specialties
Product Information [Line Items]
Net Sales	60,457	61,920	119,211	119,269
Gross profit (loss)	21,224	23,394	41,402	42,149
Corporate
Product Information [Line Items]
Gross profit (loss)	(5,989)	464	(9,618)	(43)
Aggregates
Product Information [Line Items]
Net Sales	481,616	421,974	813,830	685,858
Gross profit (loss)	137,272	100,142	178,690	110,194
Asphalt
Product Information [Line Items]
Net Sales	18,896	22,627	28,541	33,125
Gross profit (loss)	4,314	4,869	2,851	3,443
Ready Mixed Concrete
Product Information [Line Items]
Net Sales	149,750	52,379	277,323	90,388
Gross profit (loss)	9,341	6,982	11,424	9,926
Road Paving
Product Information [Line Items]
Net Sales	39,125	43,037	46,249	52,975
Gross profit (loss)	$ 3,577	$ (249)	$ 265	$ (4,231)

Components of Change in Other Assets and Liabilities Net (Detail) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Supplemental Cash Flow Elements [Abstract]
Other current and noncurrent assets	$ (5,501)	$ (6,139)
Accrued salaries, benefits and payroll taxes	(13,794)	(755)
Accrued insurance and other taxes	(1,278)	3,911
Accrued income taxes	(19,902)	16,678
Accrued pension, postretirement and postemployment benefits	16,283	4,281
Other current and noncurrent liabilities	(4,878)	(389)
Change in other assets and liabilities	$ (29,070)	$ 17,587

Noncash Investing and Financing Activities (Detail) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Supplemental Cash Flow Elements [Abstract]
Acquisition of assets through capital lease	$ 1,331	$ 6,333
Acquisition of assets through asset exchange	$ 5,000