Martin Marietta Materials (MLM) 10-Q 5 May 15 2015 Q1 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	3 Months Ended
	Mar. 31, 2015	1-May-15
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	FALSE
Document Period End Date	31-Mar-15
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q1
Trading Symbol	MLM
Entity Registrant Name	MARTIN MARIETTA MATERIALS INC
Entity Central Index Key	916076
Current Fiscal Year End Date	-19
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		67,481,231

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014
In Thousands, unless otherwise specified
Current Assets:
Cash and cash equivalents	$56,366	$108,651	$35,801
Accounts receivable, net	381,389	421,001	242,587
Inventories, net	505,047	484,919	354,718
Current deferred income tax benefits	235,367	244,638	73,320
Other current assets	103,560	29,607	51,788
Total Current Assets	1,281,729	1,288,816	758,214
Property, plant and equipment	5,694,546	5,691,676	4,001,505
Allowances for depreciation, depletion and amortization	-2,329,440	-2,288,906	-2,207,969
Net property, plant and equipment	3,365,106	3,402,770	1,793,536
Goodwill	2,071,471	2,068,799	616,621
Other noncurrent assets	107,386	108,802	39,143
Total Assets	7,417,646	7,464,392	3,255,257
Current Liabilities:
Bank overdraft		183
Accounts payable	184,066	202,476	98,775
Accrued salaries, benefits and payroll taxes	23,590	36,576	12,904
Pension and postretirement benefits	6,637	6,953	2,356
Accrued insurance and other taxes	58,742	58,356	27,265
Current maturities of long-term debt and short-term facilities	14,406	14,336	12,403
Accrued interest	22,461	16,136	18,077
Other current liabilities	33,653	61,632	21,978
Total Current Liabilities	343,555	396,648	193,758
Long-term debt	1,566,617	1,571,059	1,055,541
Pension, postretirement and postemployment benefits	252,923	249,333	80,457
Noncurrent deferred income taxes	753,727	734,583	272,346
Other noncurrent liabilities	158,641	160,021	108,862
Total Liabilities	3,075,463	3,111,644	1,710,964
Equity:
Common stock, par value $0.01 per share	673	671	462
Preferred stock, par value $0.01 per share
Additional paid-in capital	3,255,809	3,243,619	442,551
Accumulated other comprehensive loss	-106,723	-106,159	-42,744
Retained earnings	1,190,807	1,213,035	1,108,516
Total Shareholders' Equity	4,340,566	4,351,166	1,508,785
Noncontrolling interests	1,617	1,582	35,508
Total Equity	4,342,183	4,352,748	1,544,293
Total Liabilities and Equity	7,417,646	7,464,392	3,255,257
Operating Permits
Current Assets:
Intangibles, net	497,841	499,487	16,935
Other Intangible Assets
Current Assets:
Intangibles, net	$94,113	$95,718	$30,808

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parenthetical) (USD $)	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 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_Ear

Consolidated Statements of Earnings and Comprehensive Earnings (USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Income Statement [Abstract]
Net Sales	$631,876	$379,678
Freight and delivery revenues	59,471	48,951
Total revenues	691,347	428,629
Cost of sales	557,615	353,843
Freight and delivery costs	59,471	48,951
Total cost of revenues	617,086	402,794
Gross Profit	74,261	25,835
Selling, general & administrative expenses	49,450	34,247
Acquisition-related expenses, net	1,604	9,512
Other operating income, net	-2,364	-2,026
Earnings (Loss) from Operations	25,571	-15,898
Interest expense	19,331	12,201
Other nonoperating expenses, net	893	3,463
Earnings (Loss) from continuing operations before taxes on income	5,347	-31,562
Income tax benefit	-812	-8,424
Earnings (Loss) from Continuing Operations	6,159	-23,138
Loss on discontinued operations, net of related tax benefit of $1		-15
Consolidated net earnings (loss)	6,159	-23,153
Less: Net earnings (loss) attributable to noncontrolling interests	33	-1,535
Net Earnings (Loss) Attributable to Martin Marietta Materials, Inc.	6,126	-21,618
Net Earnings (Loss) Attributable to Martin Marietta Materials, Inc.:
Earnings (Loss) from continuing operations	6,126	-21,603
Loss from discontinued operations		-15
Net Earnings (Loss) Attributable to Martin Marietta Materials, Inc.	6,126	-21,618
Consolidated Comprehensive Earnings (Loss): (See Note 1)
Earnings (Loss) attributable to Martin Marietta Materials, Inc.	5,562	-20,248
Earnings (Loss) attributable to noncontrolling interests	35	-1,534
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	$5,597	($21,782)
Net Earnings (Loss) Attributable to Martin Marietta Materials, Inc. per common share
Basic from continuing operations attributable to common shareholders	$0.07	($0.47)
Earnings Per Share, Basic, Total	$0.07	($0.47)
Diluted from continuing operations attributable to common shareholders	$0.07	($0.47)
Earnings Per Share, Diluted, Total	$0.07	($0.47)
Weighted-Average Common Shares Outstanding:
Basic	67,411	46,315
Diluted	67,676	46,315
Cash Dividends Per Common Share	$0.40	$0.40

Consolidated_Statements_of_Ear1

Consolidated Statements of Earnings and Comprehensive Earnings (Parenthetical) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014
Income Statement [Abstract]
Loss on discontinued operations, related tax benefit	$1

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Cash Flows from Operating Activities:
Consolidated net earnings (loss)	$6,159	($23,153)
Adjustments to reconcile consolidated net earnings (loss) to net cash provided by operating activities:
Depreciation, depletion and amortization	67,268	42,466
Stock-based compensation expense	2,907	1,409
Gains on divestitures and sales of assets	-1,576	-1,106
Deferred income taxes	27,774	-5,063
Excess tax benefits from stock-based compensation transactions	-109	-636
Other items, net	1,192	1,223
Changes in operating assets and liabilities, net of effects of acquisitions and divestitures:
Accounts receivable, net	40,006	2,834
Inventories, net	-19,071	-7,411
Accounts payable	-20,328	-4,825
Other assets and liabilities, net	-69,097	874
Net Cash Provided by Operating Activities	35,125	6,612
Cash Flows from Investing Activities:
Additions to property, plant and equipment	-56,085	-36,913
Acquisitions, net	-10,589	-50
Proceeds from divestitures and sales of assets	1,475	1,401
Repayments from affiliate	1,808
Net Cash Used for Investing Activities	-63,391	-35,562
Cash Flows from Financing Activities:
Borrowings of long-term debt		60,000
Repayments of long-term debt	-4,738	-23,125
Payments on capital lease obligations	-795	-525
Change in bank overdraft	-183	-2,556
Dividends paid	-28,354	-18,604
Issuances of common stock	9,942	6,488
Excess tax benefits from stock-based compensation transactions	109	636
Net Cash (Used for) Provided by Financing Activities	-24,019	22,314
Net Decrease in Cash and Cash Equivalents	-52,285	-6,636
Cash and Cash Equivalents, beginning of period	108,651	42,437
Cash and Cash Equivalents, end of period	56,366	35,801
Supplemental Disclosures of Cash Flow Information:
Cash paid for interest	11,417	1,633
Cash paid for income taxes	$18,678	$53

Consolidated_Statement_of_Tota

Consolidated Statement of Total Equity (USD $)	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Loss	Retained Earnings	Total Shareholders' Equity	Noncontrolling Interests
In Thousands, except Share data
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	6,159				6,126	6,126	33
Other comprehensive (loss) earnings	-562			-564		-564	2
Dividends declared	-28,354				-28,354	-28,354
Issuances of common stock for stock award plans	9,286	2	9,284			9,286
Issuances of common stock for stock award plans (in shares)		182,000
Stock-based compensation expense	2,906		2,906			2,906
Ending Balance at Mar. 31, 2015	$4,342,183	$673	$3,255,809	($106,723)	$1,190,807	$4,340,566	$1,617
Ending Balance (in shares) at Mar. 31, 2015		67,475,000

Significant_Accounting_Policie

Significant Accounting Policies	3 Months Ended
	Mar. 31, 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,		Alabama, Florida, Georgia, Mississippi, Tennessee, Nova Scotia and the Bahamas	Arkansas, Colorado, southern Kansas,
			northern Kansas, Kentucky, Maryland, Minnesota, Missouri,			Louisiana, western Nebraska, Nevada, Oklahoma, Texas, Utah
			eastern Nebraska, North Carolina, Ohio,			and Wyoming
			South Carolina,
			Virginia, Washington and
			West Virginia
	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 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 three months ended March 31, 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, 2016 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 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
			March 31,
			2015			2014
			(Dollars in Thousands)
	Net earnings (loss) attributable to Martin Marietta Materials, Inc.		$	6,126		$	(21,618	)
	Other comprehensive (loss) earnings, net of tax			(564	)		1,370
	Comprehensive earnings (loss) attributable to Martin Marietta Materials, Inc.		$	5,562		$	(20,248	)
	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
			March 31,
			2015			2014
			(Dollars in Thousands)
	Net earnings (loss) attributable to noncontrolling interests		$	33		$	(1,535	)
	Other comprehensive earnings, net of tax			2			1
	Comprehensive earnings (loss) attributable to noncontrolling interests		$	35		$	(1,534	)
	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 March 31, 2015
	Balance at beginning of period		$	(106,688	)	$	3,278		$	(2,749	)	$	(106,159	)
	Other comprehensive loss before reclassifications, net of tax			—			(2,288	)		—			(2,288	)
	Amounts reclassified from accumulated other comprehensive loss, net of tax			1,537			—			187			1,724
	Other comprehensive earnings (loss), net of tax			1,537			(2,288	)		187			(564	)
	Balance at end of period		$	(105,151	)	$	990		$	(2,562	)	$	(106,723	)
			Three Months Ended March 31, 2014
	Balance at beginning of period		$	(44,549	)	$	3,902		$	(3,467	)	$	(44,114	)
	Other comprehensive earnings before reclassifications, net of tax			—			914			—			914
	Amounts reclassified from accumulated other comprehensive loss, net of tax			282			—			174			456
	Other comprehensive earnings, net of tax			282			914			174			1,370
	Balance at end of period		$	(44,267	)	$	4,816		$	(3,293	)	$	(42,744	)
	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)
					Unamortized
					Value of			Net
		Pension and			Terminated			Noncurrent
		Postretirement			Forward Starting			Deferred Tax
		Benefit Plans			Interest Rate Swap			Assets
		Three Months Ended March 31, 2015
Balance at beginning of period		$	68,568		$	1,799		$	70,367
Tax effect of other comprehensive earnings			(1,016	)		(120	)		(1,136	)
Balance at end of period		$	67,552		$	1,679		$	69,231
		Three Months Ended March 31, 2014
Balance at beginning of period		$	29,198		$	2,269		$	31,467
Tax effect of other comprehensive earnings			(182	)		(114	)		(296	)
Balance at end of period		$	29,016		$	2,155		$	31,171
Reclassifications out of accumulated other comprehensive loss are as follows:
		Three Months Ended						Affected line items in the
		March 31,						consolidated statements of earnings
		2015			2014			and comprehensive earnings
		(Dollars in Thousands)
Pension and postretirement benefit plans
Amortization of:
Prior service credit		$	(471	)	$	(703	)
Actuarial loss			3,026			1,167
			2,555			464		Cost of sales; Selling, general
								and administrative expenses
Tax benefit			(1,016	)		(182	)	Income tax benefit
		$	1,539		$	282
Unamortized value of terminated forward starting interest
rate swap
Additional interest expense		$	307		$	288		Interest expense
Tax benefit			(120	)		(114	)	Income tax benefit
		$	187		$	174
1	Significant Accounting Policies (continued)
Earnings (Loss) 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 months ended March 31, 2015, 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. For the three months ended March 31, 2014, all such awards were antidilutive given the net loss attributable to Martin Marietta.
The following table reconciles the numerator and denominator for basic and diluted earnings (loss) per common share:
		Three Months Ended
		March 31,
		2015			2014
		(In Thousands)
Net earnings (loss) from continuing operations attributable to		$	6,126		$	(21,603	)
Martin Marietta Materials, Inc.
Less: Distributed and undistributed earnings attributable to unvested awards			1,369			67
Basic and diluted net earnings (loss) available to common shareholders from			4,757			(21,670	)
continuing operations attributable to Martin Marietta Materials, Inc.
Basic and diluted net loss available to common shareholders from			—			(15	)
discontinued operations
Basic and diluted net earnings (loss) available to common shareholders		$	4,757		$	(21,685	)
attributable to Martin Marietta Materials, Inc.
Basic weighted-average common shares outstanding			67,411			46,315
Effect of dilutive employee and director awards			265			—
Diluted weighted-average common shares outstanding			67,676			46,315

Business_Combinations_and_Asse

Business Combinations and Assets Held For Sale	3 Months Ended
	Mar. 31, 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.  The Corporation has determined preliminary fair values of the assets acquired and liabilities assumed.  Although initial accounting for the business combination has been recorded, certain amounts are subject to change based on the additional reviews performed, such as asset and liability verification.  Specific accounts subject to ongoing purchase accounting adjustments include, but are not limited to, parts and supplies inventories; property, plant and equipment; other assets; goodwill; accounts payable; and deferred taxes.  Therefore, the measurement period remains open as of March 31, 2015.
	Total revenues and earnings from operations included in the Corporation’s consolidated statement of earnings attributable to TXI operations as of March 31, 2015 are $224,059,000 and $9,314,000, respectively.
	Acquisition integration expenses related to the TXI acquisition were $1,451,000 for the three months ended March 31, 2015.
	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 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 result from the combination.  These amounts are reflected in the pro forma earnings for the quarter ended March 31, 2014.
	The unaudited pro forma financial information for the three months ended March 31, 2014 includes TXI’s historical operating results for the three months ended February 28, 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 as 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 at the beginning of fiscal year 2014.
			Three Months Ended
			March 31, 2014
			(Dollars in Thousands)
	Net sales		$	563,228
	Loss from continuing operations attributable to controlling interest		$	(74,591	)
	2	Business Combinations and Assets Held for Sale (continued)
	Assets Held for Sale
	At March 31, 2015, the Corporation classified certain land at its Crestmore facility in California as assets held for sale.  The land held for sale is included in other current assets on the consolidated balance sheet and has been reported as an asset within the Cement Group segment in Note 9.

Inventories_Net

Inventories, Net	3 Months Ended
	Mar. 31, 2015
Inventory Disclosure [Abstract]
Inventories, Net	3	Inventories, Net
			March 31,			December 31,			March 31,
			2015			2014			2014
			(Dollars in Thousands)
	Finished products		$	428,783		$	413,766		$	372,567
	Products in process and raw materials			70,558			65,250			16,478
	Supplies and expendable parts			125,547			125,092			64,093
				624,888			604,108			453,138
	Less: Allowances			(119,841	)		(119,189	)		(98,420	)
	Total		$	505,047		$	484,919		$	354,718

LongTerm_Debt

Long-Term Debt	3 Months Ended
	Mar. 31, 2015
Debt Disclosure [Abstract]
Long-Term Debt	4	Long-Term Debt
	`		March 31,			December 31,			March 31,
			2015			2014			2014
			(Dollars in Thousands)
	6.6% Senior Notes, due 2018		$	299,182		$	299,123		$	298,949
	7% Debentures, due 2025			124,508			124,500			124,478
	6.25% Senior Notes, due 2037			228,194			228,184			228,157
	4.25% Senior Notes, due 2024			395,410			395,309			—
	Floating Rate Notes, due 2017, interest rate of 1.36% and			298,980			298,869			—
	1.33% at March 31, 2015 and December 31, 2014, respectively
	Term Loan Facility, due 2018, interest rate of 1.67% at March 31,			233,213			236,258			245,395
	2015 and December 31, 2014; and 1.65% at March 31, 2014
	Revolving Facility, interest rate of 1.89% at March 31, 2014			—			—			20,000
	Trade Receivable Facility, interest rate of 0.75% at March 31, 2014			—			—			150,000
	Other notes			1,536			3,152			965
	Total debt			1,581,023			1,585,395			1,067,944
	Less: Current maturities			(14,406	)		(14,336	)		(12,403	)
	Long-term debt		$	1,566,617		$	1,571,059		$	1,055,541
	4	Long-Term Debt (continued)
	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, National Association 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 $339,086,000, $369,575,000 and $232,566,000 at March 31, 2015, December 31, 2014 and March 31, 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 $280,101,000, $313,428,000 and $177,233,000 at March 31, 2015, December 31, 2014 and March 31, 2014, respectively.  The Trade Receivable Facility contains a cross-default provision to the Corporation’s other debt agreements.
	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 March 31, 2015.
	Available borrowings under the Revolving Facility are reduced by any outstanding letters of credit issued by the Corporation under the Revolving Facility. At March 31, 2015, December 31, 2014 and March 31, 2014, the Corporation had $2,507,000 of outstanding letters of credit issued under the Revolving Facility.
	4.Long-Term Debt (continued)
	Accumulated other comprehensive loss includes the unamortized value of terminated forward starting interest rate swap agreements. For the three months ended March 31, 2015, the Corporation recognized $307,000 as additional interest expense. For the three months ended March 31, 2014, the Corporation recognized $288,000 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

Financial Instruments	3 Months Ended
	Mar. 31, 2015
Fair Value Disclosures [Abstract]
Financial Instruments	5	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.
	Accounts receivables are due from a large number of customers, primarily in the construction industry, and are dispersed across wide geographic and economic regions. However, accounts receivables are more heavily concentrated in certain states (namely, Texas, Colorado, North Carolina, Iowa and Georgia). The estimated fair values of accounts receivables approximate their carrying amounts due to the short-term nature of the receivables.
	Notes receivables are primarily promissory notes with customers and are not publicly traded. Management estimates that the fair value of notes receivables approximates the carrying amount. The estimated fair values of notes receivables 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. The estimated fair value of the bank overdraft approximates its carrying amount 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 amounts due to the short-term nature of the payables.
	The carrying values and fair values of the Corporation’s long-term debt were $1,581,023,000 and $1,691,478,000, respectively, at March 31, 2015; $1,585,395,000 and $1,680,584,000, respectively, at December 31, 2014; and $1,067,944,000 and $1,127,149,000, respectively, at March 31, 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.

Income_Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2015
Income Tax Disclosure [Abstract]
Income Taxes	6	Income Taxes
			Three Months Ended March 31,
			2015				2014
	Estimated effective income tax rate:
	Continuing operations			(15.2	)	%		26.7	%
	Discontinued operations			—		%		6.3	%
	Consolidated overall			(15.2	)	%		26.7	%
	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 rates 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 decrease in the effective income tax rate is attributable to discrete events, which include the exercise of converted stock awards issued to former TXI personnel.  Excluding discrete items, the estimated effective income tax rate would have been 31%, in line with annual guidance.  For the year, the Corporation expects to utilize net operating loss, or NOL, carryforwards acquired with TXI.
	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_Ben

Pension and Postretirement Benefits	3 Months Ended
	Mar. 31, 2015
Compensation And Retirement Disclosure [Abstract]
Pension and Postretirement Benefits	7	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 March 31,
			Pension						Postretirement Benefits
			2015			2014			2015			2014
			(Dollars in Thousands)
	Service cost		$	6,290		$	3,730		$	39		$	55
	Interest cost			8,112			6,590			230			290
	Expected return on assets			(9,104	)		(7,698	)		—			—
	Amortization of:
	Prior service cost (credit)			105			111			(576	)		(814	)
	Actuarial loss (gain)			3,108			1,202			(82	)		(35	)
	Termination benefit charge			256			—			—			—
	Net periodic benefit cost (credit)		$	8,767		$	3,935		$	(389	)	$	(504	)

Commitments_and_Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2015
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	8	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.
	The Corporation had 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 the quarter ended March 31, 2015.  As of December 31, 2014 and March 31, 2014, the amount due from the affiliate related to this loan was $1,808,000 and $2,773,000, respectively.
	In addition, the Corporation has a $6,000,000 outstanding loan due from this unconsolidated affiliate as of March 31, 2015, December 31, 2014 and March 31, 2014.
	Employees
	Approximately 13% 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 and the 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 2015, and management does not anticipate any difficulties renewing this labor contract.  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 2015. Management does not anticipate any difficulties in renewing this labor contract. The Woodville collective bargaining agreement expires in May 2018.

Business_Segments

Business Segments	3 Months Ended
	Mar. 31, 2015
Segment Reporting [Abstract]
Business Segments	9	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 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.
	9	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
			March 31,
			2015			2014
			(Dollars in Thousands)
	Total revenues:
	Mid-America Group		$	140,834		$	115,708
	Southeast Group			64,678			59,820
	West Group			320,571			190,787
	Total Aggregates Business			526,083			366,315
	Cement			102,100			—
	Magnesia Specialties			63,164			62,314
	Total		$	691,347		$	428,629
	Net sales:
	Mid-America Group		$	129,705		$	106,533
	Southeast Group			59,770			55,381
	West Group			287,082			160,416
	Total Aggregates Business			476,557			322,330
	Cement			96,565			—
	Magnesia Specialties			58,754			57,348
	Total		$	631,876		$	379,678
	(Loss) Earnings from operations:
	Mid-America Group		$	(4,203	)	$	(11,766	)
	Southeast Group			(1,548	)		(6,111	)
	West Group			14,499			2,081
	Total Aggregates Business			8,748			(15,796	)
	Cement			12,229			—
	Magnesia Specialties			17,789			16,285
	Corporate			(13,195	)		(16,387	)
	Total		$	25,571		$	(15,898	)
	9	Business Segments (continued)
	Cement intersegment sales, which are to the ready mixed concrete product line in the West Group, were $18,377,000 for the three months ended March 31, 2015.
			March 31,			December 31,			March 31,
			2015			2014			2014
			(Dollars in Thousands)
	Assets employed:
	Mid-America Group		$	1,287,933		$	1,290,833		$	1,257,753
	Southeast Group			597,461			604,044			607,219
	West Group			2,490,726			2,444,400			1,024,038
	Total Aggregates Business			4,376,120			4,339,277			2,889,010
	Cement			2,422,119			2,451,799			—
	Magnesia Specialties			147,745			150,359			153,070
	Corporate			471,662			522,957			213,177
	Total		$	7,417,646		$	7,464,392		$	3,255,257
	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.
	9	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
			March 31,
			2015			2014
			(Dollars in Thousands)
	Net sales:
	Aggregates		$	332,214		$	263,885
	Asphalt			9,645			10,498
	Ready Mixed Concrete			127,572			38,009
	Road Paving			7,126			9,938
	Total Aggregates Business			476,557			322,330
	Cement			96,565		—
	Magnesia Specialties			58,754			57,348
	Total		$	631,876		$	379,678
	Gross profit (loss):
Aggregates		$	41,417		$	10,051
Asphalt			(1,463	)		(1,426	)
Ready Mixed Concrete			2,084			2,944
Road Paving			(3,311	)		(3,982	)
Total Aggregates Business			38,727			7,587
Cement			18,985			—
Magnesia Specialties			20,178			18,755
Corporate			(3,629	)		(507	)
Total		$	74,261		$	25,835

Supplemental_Cash_Flow_Informa

Supplemental Cash Flow Information	3 Months Ended
	Mar. 31, 2015
Supplemental Cash Flow Elements [Abstract]
Supplemental Cash Flow Information	10	Supplemental Cash Flow Information
	The components of the change in other assets and liabilities, net, are as follows:
			Three Months Ended
			March 31,
			2015			2014
			(Dollars in Thousands)
	Other current and noncurrent assets		$	(4,083	)	$	(783	)
	Accrued salaries, benefits and payroll taxes			(13,703	)		(3,984	)
	Accrued insurance and other taxes			386			(1,838	)
	Accrued income taxes			(46,700	)		(4,595	)
	Accrued pension, postretirement and postemployment benefits			5,830			2,763
	Other current and noncurrent liabilities			(10,827	)		9,311
			$	(69,097	)	$	874
	The decrease in the accrued salaries, benefits and payroll taxes is primarily attributable to a decrease in TXI acquisition-related accrued severance expense.  The change in accrued income taxes is primarily due to an increase in income tax benefit of $23,300,000.  Other current and noncurrent liabilities decreased due to a reduction of accrued interest expense attributable to payments made in 2015 by $4,403,000 and a decrease in book overdraft by $5,724,000.
	Noncash investing and financing activities are as follows:
			Three Months Ended
			March 31,
			2015			2014
			(Dollars in Thousands)
	Noncash investing and financing activities:
	Acquisition of assets through capital lease		$	1,222		$	5,930
	Acquisition of assets through asset exchange		$	5,153		$	—

Significant_Accounting_Policie1

Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2015
Accounting Policies [Abstract]
Organization	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,		Alabama, Florida, Georgia, Mississippi, Tennessee, Nova Scotia and the Bahamas	Arkansas, Colorado, southern Kansas,
			northern Kansas, Kentucky, Maryland, Minnesota, Missouri,			Louisiana, western Nebraska, Nevada, Oklahoma, Texas, Utah
			eastern Nebraska, North Carolina, Ohio,			and Wyoming
			South Carolina,
			Virginia, Washington and
			West Virginia
	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 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.
Basis of Presentation	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 three months ended March 31, 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	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, 2016 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 results of operations.
Consolidated Comprehensive Earnings/Loss and Accumulated Other Comprehensive Loss	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
			March 31,
			2015			2014
			(Dollars in Thousands)
	Net earnings (loss) attributable to Martin Marietta Materials, Inc.		$	6,126		$	(21,618	)
	Other comprehensive (loss) earnings, net of tax			(564	)		1,370
	Comprehensive earnings (loss) attributable to Martin Marietta Materials, Inc.		$	5,562		$	(20,248	)
	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
			March 31,
			2015			2014
			(Dollars in Thousands)
	Net earnings (loss) attributable to noncontrolling interests		$	33		$	(1,535	)
	Other comprehensive earnings, net of tax			2			1
	Comprehensive earnings (loss) attributable to noncontrolling interests		$	35		$	(1,534	)
	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 March 31, 2015
	Balance at beginning of period		$	(106,688	)	$	3,278		$	(2,749	)	$	(106,159	)
	Other comprehensive loss before reclassifications, net of tax			—			(2,288	)		—			(2,288	)
	Amounts reclassified from accumulated other comprehensive loss, net of tax			1,537			—			187			1,724
	Other comprehensive earnings (loss), net of tax			1,537			(2,288	)		187			(564	)
	Balance at end of period		$	(105,151	)	$	990		$	(2,562	)	$	(106,723	)
			Three Months Ended March 31, 2014
	Balance at beginning of period		$	(44,549	)	$	3,902		$	(3,467	)	$	(44,114	)
	Other comprehensive earnings before reclassifications, net of tax			—			914			—			914
	Amounts reclassified from accumulated other comprehensive loss, net of tax			282			—			174			456
	Other comprehensive earnings, net of tax			282			914			174			1,370
	Balance at end of period		$	(44,267	)	$	4,816		$	(3,293	)	$	(42,744	)
	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)
						Unamortized
						Value of			Net
			Pension and			Terminated			Noncurrent
			Postretirement			Forward Starting			Deferred Tax
			Benefit Plans			Interest Rate Swap			Assets
			Three Months Ended March 31, 2015
	Balance at beginning of period		$	68,568		$	1,799		$	70,367
	Tax effect of other comprehensive earnings			(1,016	)		(120	)		(1,136	)
	Balance at end of period		$	67,552		$	1,679		$	69,231
			Three Months Ended March 31, 2014
	Balance at beginning of period		$	29,198		$	2,269		$	31,467
	Tax effect of other comprehensive earnings			(182	)		(114	)		(296	)
	Balance at end of period		$	29,016		$	2,155		$	31,171
	Reclassifications out of accumulated other comprehensive loss are as follows:
			Three Months Ended						Affected line items in the
			March 31,						consolidated statements of earnings
			2015			2014			and comprehensive earnings
			(Dollars in Thousands)
	Pension and postretirement benefit plans
	Amortization of:
Prior service credit		$	(471	)	$	(703	)
Actuarial loss			3,026			1,167
			2,555			464		Cost of sales; Selling, general
								and administrative expenses
Tax benefit			(1,016	)		(182	)	Income tax benefit
		$	1,539		$	282
Unamortized value of terminated forward starting interest
rate swap
Additional interest expense		$	307		$	288		Interest expense
Tax benefit			(120	)		(114	)	Income tax benefit
		$	187		$	174
Earnings (Loss) per Common Share	Earnings (Loss) 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 months ended March 31, 2015, 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. For the three months ended March 31, 2014, all such awards were antidilutive given the net loss attributable to Martin Marietta.
	The following table reconciles the numerator and denominator for basic and diluted earnings (loss) per common share:
			Three Months Ended
			March 31,
			2015			2014
			(In Thousands)
	Net earnings (loss) from continuing operations attributable to		$	6,126		$	(21,603	)
	Martin Marietta Materials, Inc.
	Less: Distributed and undistributed earnings attributable to unvested awards			1,369			67
	Basic and diluted net earnings (loss) available to common shareholders from			4,757			(21,670	)
	continuing operations attributable to Martin Marietta Materials, Inc.
	Basic and diluted net loss available to common shareholders from			—			(15	)
	discontinued operations
	Basic and diluted net earnings (loss) available to common shareholders		$	4,757		$	(21,685	)
	attributable to Martin Marietta Materials, Inc.
	Basic weighted-average common shares outstanding			67,411			46,315
	Effect of dilutive employee and director awards			265			—
	Diluted weighted-average common shares outstanding			67,676			46,315

Significant_Accounting_Policie2

Significant Accounting Policies (Tables)	3 Months Ended
	Mar. 31, 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 March 31, 2015
	Balance at beginning of period	$	(106,688	)	$	3,278		$	(2,749	)	$	(106,159	)
	Other comprehensive loss before reclassifications, net of tax		—			(2,288	)		—			(2,288	)
	Amounts reclassified from accumulated other comprehensive loss, net of tax		1,537			—			187			1,724
	Other comprehensive earnings (loss), net of tax		1,537			(2,288	)		187			(564	)
	Balance at end of period	$	(105,151	)	$	990		$	(2,562	)	$	(106,723	)
		Three Months Ended March 31, 2014
	Balance at beginning of period	$	(44,549	)	$	3,902		$	(3,467	)	$	(44,114	)
	Other comprehensive earnings before reclassifications, net of tax		—			914			—			914
	Amounts reclassified from accumulated other comprehensive loss, net of tax		282			—			174			456
	Other comprehensive earnings, net of tax		282			914			174			1,370
	Balance at end of period	$	(44,267	)	$	4,816		$	(3,293	)	$	(42,744	)
Noncurrent Deferred Tax Assets Recorded In Accumulated Other Comprehensive Loss	Changes in net noncurrent deferred tax assets recorded in accumulated other comprehensive loss are as follows:
		(Dollars in Thousands)
					Unamortized
					Value of			Net
		Pension and			Terminated			Noncurrent
		Postretirement			Forward Starting			Deferred Tax
		Benefit Plans			Interest Rate Swap			Assets
		Three Months Ended March 31, 2015
	Balance at beginning of period	$	68,568		$	1,799		$	70,367
	Tax effect of other comprehensive earnings		(1,016	)		(120	)		(1,136	)
	Balance at end of period	$	67,552		$	1,679		$	69,231
		Three Months Ended March 31, 2014
	Balance at beginning of period	$	29,198		$	2,269		$	31,467
	Tax effect of other comprehensive earnings		(182	)		(114	)		(296	)
	Balance at end of period	$	29,016		$	2,155		$	31,171
Reclassification Out of Accumulated Other Comprehensive Loss	Reclassifications out of accumulated other comprehensive loss are as follows:
		Three Months Ended						Affected line items in the
		March 31,						consolidated statements of earnings
		2015			2014			and comprehensive earnings
		(Dollars in Thousands)
	Pension and postretirement benefit plans
	Amortization of:
	Prior service credit	$	(471	)	$	(703	)
	Actuarial loss		3,026			1,167
			2,555			464		Cost of sales; Selling, general
								and administrative expenses
	Tax benefit		(1,016	)		(182	)	Income tax benefit
		$	1,539		$	282
	Unamortized value of terminated forward starting interest
	rate swap
	Additional interest expense	$	307		$	288		Interest expense
	Tax benefit		(120	)		(114	)	Income tax benefit
		$	187		$	174
Basic and Diluted Earnings (Loss) per Common Share	The following table reconciles the numerator and denominator for basic and diluted earnings (loss) per common share:
		Three Months Ended
		March 31,
		2015			2014
		(In Thousands)
	Net earnings (loss) from continuing operations attributable to	$	6,126		$	(21,603	)
	Martin Marietta Materials, Inc.
	Less: Distributed and undistributed earnings attributable to unvested awards		1,369			67
	Basic and diluted net earnings (loss) available to common shareholders from		4,757			(21,670	)
	continuing operations attributable to Martin Marietta Materials, Inc.
	Basic and diluted net loss available to common shareholders from		—			(15	)
	discontinued operations
	Basic and diluted net earnings (loss) available to common shareholders	$	4,757		$	(21,685	)
	attributable to Martin Marietta Materials, Inc.
	Basic weighted-average common shares outstanding		67,411			46,315
	Effect of dilutive employee and director awards		265			—
	Diluted weighted-average common shares outstanding		67,676			46,315
Parent
Significant Accounting Policies [Line Items]
Comprehensive Earnings (Loss)	Comprehensive earnings attributable to Martin Marietta is as follows:
		Three Months Ended
		March 31,
		2015			2014
		(Dollars in Thousands)
	Net earnings (loss) attributable to Martin Marietta Materials, Inc.	$	6,126		$	(21,618	)
	Other comprehensive (loss) earnings, net of tax		(564	)		1,370
	Comprehensive earnings (loss) attributable to Martin Marietta Materials, Inc.	$	5,562		$	(20,248	)
Noncontrolling Interests
Significant Accounting Policies [Line Items]
Comprehensive Earnings (Loss)	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
		March 31,
		2015			2014
		(Dollars in Thousands)
	Net earnings (loss) attributable to noncontrolling interests	$	33		$	(1,535	)
	Other comprehensive earnings, net of tax		2			1
	Comprehensive earnings (loss) attributable to noncontrolling interests	$	35		$	(1,534	)

Business_Combinations_and_Asse1

Business Combinations and Assets Held for Sale (Tables)	3 Months Ended
	Mar. 31, 2015
Business Combinations [Abstract]
Pro Forma Financial Information	The pro forma financial information as 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 at the beginning of fiscal year 2014.
		Three Months Ended
		March 31, 2014
		(Dollars in Thousands)
	Net sales	$	563,228
	Loss from continuing operations attributable to controlling interest	$	(74,591	)

Inventories_Net_Tables

Inventories, Net (Tables)	3 Months Ended
	Mar. 31, 2015
Inventory Disclosure [Abstract]
Schedule of Inventories Net
		March 31,			December 31,			March 31,
		2015			2014			2014
		(Dollars in Thousands)
	Finished products	$	428,783		$	413,766		$	372,567
	Products in process and raw materials		70,558			65,250			16,478
	Supplies and expendable parts		125,547			125,092			64,093
			624,888			604,108			453,138
	Less: Allowances		(119,841	)		(119,189	)		(98,420	)
	Total	$	505,047		$	484,919		$	354,718

LongTerm_Debt_Tables

Long-Term Debt (Tables)	3 Months Ended
	Mar. 31, 2015
Debt Disclosure [Abstract]
Long-Term Debt
	`	March 31,			December 31,			March 31,
		2015			2014			2014
		(Dollars in Thousands)
	6.6% Senior Notes, due 2018	$	299,182		$	299,123		$	298,949
	7% Debentures, due 2025		124,508			124,500			124,478
	6.25% Senior Notes, due 2037		228,194			228,184			228,157
	4.25% Senior Notes, due 2024		395,410			395,309			—
	Floating Rate Notes, due 2017, interest rate of 1.36% and		298,980			298,869			—
	1.33% at March 31, 2015 and December 31, 2014, respectively
	Term Loan Facility, due 2018, interest rate of 1.67% at March 31,		233,213			236,258			245,395
	2015 and December 31, 2014; and 1.65% at March 31, 2014
	Revolving Facility, interest rate of 1.89% at March 31, 2014		—			—			20,000
	Trade Receivable Facility, interest rate of 0.75% at March 31, 2014		—			—			150,000
	Other notes		1,536			3,152			965
	Total debt		1,581,023			1,585,395			1,067,944
	Less: Current maturities		(14,406	)		(14,336	)		(12,403	)
	Long-term debt	$	1,566,617		$	1,571,059		$	1,055,541

Income_Taxes_Tables

Income Taxes (Tables)	3 Months Ended
	Mar. 31, 2015
Income Tax Disclosure [Abstract]
Schedule of Estimated Effective Income Tax Rate
		Three Months Ended March 31,
		2015				2014
	Estimated effective income tax rate:
	Continuing operations		(15.2	)	%		26.7	%
	Discontinued operations		—		%		6.3	%
	Consolidated overall		(15.2	)	%		26.7	%

Pension_and_Postretirement_Ben1

Pension and Postretirement Benefits (Tables)	3 Months Ended
	Mar. 31, 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 March 31,
		Pension						Postretirement Benefits
		2015			2014			2015			2014
		(Dollars in Thousands)
	Service cost	$	6,290		$	3,730		$	39		$	55
	Interest cost		8,112			6,590			230			290
	Expected return on assets		(9,104	)		(7,698	)		—			—
	Amortization of:
	Prior service cost (credit)		105			111			(576	)		(814	)
	Actuarial loss (gain)		3,108			1,202			(82	)		(35	)
	Termination benefit charge		256			—			—			—
	Net periodic benefit cost (credit)	$	8,767		$	3,935		$	(389	)	$	(504	)

Business_Segments_Tables

Business Segments (Tables)	3 Months Ended
	Mar. 31, 2015
Segment Reporting [Abstract]
Financial Data for Continuing Operation For Corporation's Reportable Business Segments	9	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
			March 31,
			2015			2014
			(Dollars in Thousands)
	Total revenues:
	Mid-America Group		$	140,834		$	115,708
	Southeast Group			64,678			59,820
	West Group			320,571			190,787
	Total Aggregates Business			526,083			366,315
	Cement			102,100			—
	Magnesia Specialties			63,164			62,314
	Total		$	691,347		$	428,629
	Net sales:
	Mid-America Group		$	129,705		$	106,533
	Southeast Group			59,770			55,381
	West Group			287,082			160,416
	Total Aggregates Business			476,557			322,330
	Cement			96,565			—
	Magnesia Specialties			58,754			57,348
	Total		$	631,876		$	379,678
	(Loss) Earnings from operations:
	Mid-America Group		$	(4,203	)	$	(11,766	)
	Southeast Group			(1,548	)		(6,111	)
	West Group			14,499			2,081
	Total Aggregates Business			8,748			(15,796	)
	Cement			12,229			—
	Magnesia Specialties			17,789			16,285
	Corporate			(13,195	)		(16,387	)
	Total		$	25,571		$	(15,898	)
Asset Employed for Continuing Operations for Corporations Reportable Business Segments
			March 31,			December 31,			March 31,
			2015			2014			2014
			(Dollars in Thousands)
	Assets employed:
	Mid-America Group		$	1,287,933		$	1,290,833		$	1,257,753
	Southeast Group			597,461			604,044			607,219
	West Group			2,490,726			2,444,400			1,024,038
	Total Aggregates Business			4,376,120			4,339,277			2,889,010
	Cement			2,422,119			2,451,799			—
	Magnesia Specialties			147,745			150,359			153,070
	Corporate			471,662			522,957			213,177
	Total		$	7,417,646		$	7,464,392		$	3,255,257
Net Sales and Gross Profit by Line of Business	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
			March 31,
			2015			2014
			(Dollars in Thousands)
	Net sales:
	Aggregates		$	332,214		$	263,885
	Asphalt			9,645			10,498
	Ready Mixed Concrete			127,572			38,009
	Road Paving			7,126			9,938
	Total Aggregates Business			476,557			322,330
	Cement			96,565		—
	Magnesia Specialties			58,754			57,348
	Total		$	631,876		$	379,678
	Gross profit (loss):
	Aggregates		$	41,417		$	10,051
	Asphalt			(1,463	)		(1,426	)
	Ready Mixed Concrete			2,084			2,944
	Road Paving			(3,311	)		(3,982	)
	Total Aggregates Business			38,727			7,587
	Cement			18,985			—
	Magnesia Specialties			20,178			18,755
	Corporate			(3,629	)		(507	)
	Total		$	74,261		$	25,835

Supplemental_Cash_Flow_Informa1

Supplemental Cash Flow Information (Tables)	3 Months Ended
	Mar. 31, 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:
		Three Months Ended
		March 31,
		2015			2014
		(Dollars in Thousands)
	Other current and noncurrent assets	$	(4,083	)	$	(783	)
	Accrued salaries, benefits and payroll taxes		(13,703	)		(3,984	)
	Accrued insurance and other taxes		386			(1,838	)
	Accrued income taxes		(46,700	)		(4,595	)
	Accrued pension, postretirement and postemployment benefits		5,830			2,763
	Other current and noncurrent liabilities		(10,827	)		9,311
		$	(69,097	)	$	874
Schedule of Noncash Investing and Financing Activities
	Noncash investing and financing activities are as follows:
		Three Months Ended
		March 31,
		2015			2014
		(Dollars in Thousands)
	Noncash investing and financing activities:
	Acquisition of assets through capital lease	$	1,222		$	5,930
	Acquisition of assets through asset exchange	$	5,153		$	—

Significant_Accounting_Policie3

Significant Accounting Policies - Additional Information (Detail)	3 Months Ended	12 Months Ended
	Mar. 31, 2015	Dec. 31, 2014
	Facility
	Segment
	State
Significant Accounting Policies [Line Items]
Number of quarries distribution facilities and plants	400
Number of states with aggregates business sales by destination	32
Number of reportable segments	3
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_Attribu

Comprehensive Earnings Attributable to Martin Marietta Materials Incorporated (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Statement Of Income And Comprehensive Income [Abstract]
Net earnings (loss) attributable to Martin Marietta Materials, Inc.	$6,126	($21,618)
Other comprehensive (loss) earnings, net of tax	-564	1,370
Earnings (Loss) attributable to Martin Marietta Materials, Inc.	$5,562	($20,248)

Comprehensive_Earnings_Loss_At

Comprehensive Earnings (Loss) Attributable to Noncontrolling Interests (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Statement Of Income And Comprehensive Income [Abstract]
Net earnings (loss) attributable to noncontrolling interests	$33	($1,535)
Other comprehensive earnings, net of tax	2	1
Comprehensive earnings (loss) attributable to noncontrolling interests	$35	($1,534)

Changes_in_Accumulated_Other_C

Changes in Accumulated Other Comprehensive Earnings, Net of Tax (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	($106,159)	($44,114)
Other comprehensive loss before reclassifications, net of tax	-2,288	914
Amounts reclassified from accumulated other comprehensive loss, net of tax	1,724	456
Other comprehensive earnings (loss), net of tax	-564	1,370
Balance at end of period	-106,723	-42,744
Pension and Postretirement Benefit Plans
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	-106,688	-44,549
Amounts reclassified from accumulated other comprehensive loss, net of tax	1,537	282
Other comprehensive earnings (loss), net of tax	1,537	282
Balance at end of period	-105,151	-44,267
Foreign Currency
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	3,278	3,902
Other comprehensive loss before reclassifications, net of tax	-2,288	914
Other comprehensive earnings (loss), net of tax	-2,288	914
Balance at end of period	990	4,816
Unamortized Value of Terminated Forward Starting Interest Rate Swap
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	-2,749	-3,467
Amounts reclassified from accumulated other comprehensive loss, net of tax	187	174
Other comprehensive earnings (loss), net of tax	187	174
Balance at end of period	($2,562)	($3,293)

Noncurrent_Deferred_Tax_Assets

Noncurrent Deferred Tax Assets Recorded in Accumulated Other Comprehensive Loss (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Equity [Abstract]
Balance at beginning of period, Pension and Postretirement Benefit Plans	$68,568	$29,198
Other comprehensive earnings, tax effect, Pension and Postretirement Benefit Plans	-1,016	-182
Balance at end of period, Pension and Postretirement Benefit Plans	67,552	29,016
Balance at beginning of period, Unamortized Value of Terminated Forward Starting Interest Rate Swap	1,799	2,269
Other comprehensive earnings, tax effect, Unamortized Value of Terminated Forward Starting Interest Rate Swap	-120	-114
Balance at end of period, Unamortized Value of Terminated Forward Starting Interest Rate Swap	1,679	2,155
Balance at beginning of period, Net Non current Deferred Tax Assets	70,367	31,467
Other comprehensive earnings, tax effect, Net Non current Deferred Tax Assets	-1,136	-296
Balance at end of period, Net Non current Deferred Tax Assets	$69,231	$31,171

Reclassifications_Out_of_Accum

Reclassifications Out of Accumulated Other Comprehensive Loss (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Additional interest expense	($19,331)	($12,201)
Income tax benefit	-812	-8,424
Earnings (Loss) from Continuing Operations	6,159	-23,138
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	-471	-703
Actuarial loss	3,026	1,167
Income tax benefit	-1,016	-182
Earnings (Loss) from Continuing Operations	1,539	282
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	2,555	464
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]
Additional interest expense	307	288
Income tax benefit	-120	-114
Earnings (Loss) from Continuing Operations	$187	$174

Basic_and_Diluted_Earnings_Los

Basic and Diluted Earnings (Loss) Per Common Share (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Earnings Per Share [Abstract]
Net earnings (loss) from continuing operations attributable to Martin Marietta Materials, Inc.	$6,126	($21,603)
Less: Distributed and undistributed earnings attributable to unvested awards	1,369	67
Basic and diluted net earnings (loss) available to common shareholders from continuing operations attributable to Martin Marietta Materials, Inc.	4,757	-21,670
Basic and diluted net loss available to common shareholders from discontinued operations		-15
Basic and diluted net earnings (loss) available to common shareholders attributable to Martin Marietta Materials, Inc.	$4,757	($21,685)
Basic weighted-average common shares outstanding	67,411	46,315
Effect of dilutive employee and director awards	265
Diluted weighted-average common shares outstanding	67,676	46,315

Business_Combinations_and_Asse2

Business Combinations and Assets Held for Sale - Additional Information (Detail) (Texas Industries Inc., USD $)	3 Months Ended
	Mar. 31, 2015
Texas Industries Inc.
Business Combinations And Assets Held For Sale [Line Items]
Acquisition date	1-Jul-14
Total revenues from operations included in the consolidated statement of earnings	$224,059,000
Total earnings from operations included in the consolidated statement of earnings	9,314,000
Acquisition integration expenses	$1,451,000

Pro_Forma_Financial_Informatio

Pro Forma Financial Information (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014
Business Combinations [Abstract]
Net sales	$563,228
Loss from continuing operations attributable to controlling interest	($74,591)

Inventories_Net_Detail

Inventories Net (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014
In Thousands, unless otherwise specified
Inventory Disclosure [Abstract]
Finished products	$428,783	$413,766	$372,567
Products in process and raw materials	70,558	65,250	16,478
Supplies and expendable parts	125,547	125,092	64,093
Inventories, Gross	624,888	604,108	453,138
Less: Allowances	-119,841	-119,189	-98,420
Total	$505,047	$484,919	$354,718

Long_Term_Debt_Detail

Long Term Debt (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014
In Thousands, unless otherwise specified
Debt Instrument [Line Items]
Total debt	$1,581,023	$1,585,395	$1,067,944
Less: Current maturities	-14,406	-14,336	-12,403
Long-term debt	1,566,617	1,571,059	1,055,541
6.6% Senior Notes, Due 2018
Debt Instrument [Line Items]
Total debt	299,182	299,123	298,949
7% Debentures, Due 2025
Debt Instrument [Line Items]
Total debt	124,508	124,500	124,478
6.25% Senior Notes, Due 2037
Debt Instrument [Line Items]
Total debt	228,194	228,184	228,157
4.25% Senior Notes, Due 2024
Debt Instrument [Line Items]
Total debt	395,410	395,309
Floating Rate Notes, Due 2017
Debt Instrument [Line Items]
Total debt	298,980	298,869
Term Loan Facility, Due 2018
Debt Instrument [Line Items]
Total debt	233,213	236,258	245,395
Trade Receivable Facility
Debt Instrument [Line Items]
Credit Facility			150,000
Other Notes
Debt Instrument [Line Items]
Other notes	1,536	3,152	965
Revolving Facility
Debt Instrument [Line Items]
Credit Facility			$20,000

Long_Term_Debt_Parenthetical_D

Long Term Debt (Parenthetical) (Detail)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Revolving Facility
Debt Instrument [Line Items]
Credit Facility interest rate		1.89%
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]
Interest rate	1.36%		1.33%
Term Loan Facility, Due 2018
Debt Instrument [Line Items]
Interest rate	1.67%	1.65%	1.67%
Trade Receivable Facility
Debt Instrument [Line Items]
Credit Facility interest rate		0.75%

LongTerm_Debt_Additional_infor

Long-Term Debt - Additional information (Detail) (USD $)	3 Months Ended		12 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Debt Instrument [Line Items]
Term loan facility commitment	$250,000,000
Maximum consolidated debt reduction for unrestricted cash and cash equivalents for debt covenant calculation	200,000,000
Additional interest expense	307,000	288,000
6.6% Senior Notes, Due 2018
Debt Instrument [Line Items]
Interest rate on notes	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
Texas Industries Inc.
Debt Instrument [Line Items]
Acquisition integration expenses	1,451,000
Texas Industries Inc. | 9.25% Senior Notes due 2020
Debt Instrument [Line Items]
Interest rate on notes			9.25%
Maturity date			2020
Minimum
Debt Instrument [Line Items]
Reduction of consolidated debt in the debt ratio calculation	50,000,000
Maximum | Texas Industries Inc.
Debt Instrument [Line Items]
Amendment consolidated EBITDA			95,000,000
Acquisition integration expenses			70,000,000
Including Acquisition Bridge Debt
Debt Instrument [Line Items]
Debt covenant	3.50x
Excluding Acquisition Bridge Debt
Debt Instrument [Line Items]
Debt covenant	3.75x
Revolving Facility
Debt Instrument [Line Items]
Credit facility commitment	350,000,000
Senior unsecured revolving facility, maturity period	5 years
Outstanding letters of credit	2,507,000	2,507,000	2,507,000
Trade Receivable Facility
Debt Instrument [Line Items]
Credit facility commitment	250,000,000
Debt instrument maturity period	30-Sep-16
Eligible trade receivables	339,086,000	232,566,000	369,575,000
Credit facility borrowing base	$280,101,000	$177,233,000	313,428,000
London Interbank Offered Rate(LIBOR) | Trade Receivable Facility
Debt Instrument [Line Items]
Basis spread on variable rate	0.70%

Financial_Instruments_Addition

Financial Instruments - Additional Information (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014
Fair Value Disclosures [Abstract]
Long-term debt, carrying values	$1,581,023,000	$1,585,395,000	$1,067,944,000
Long-term debt, fair values	$1,691,478,000	$1,680,584,000	$1,127,149,000

Schedule_of_Estimated_Effectiv

Schedule of Estimated Effective Income Tax Rate (Detail)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Income Tax Disclosure [Abstract]
Continuing operations	-15.20%	26.70%
Discontinued operations		6.30%
Consolidated overall	-15.20%	26.70%

Income_Taxes_Additional_Inform

Income Taxes - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2015
Income Tax Disclosure [Abstract]
Estimated effective income tax rate, excluding discrete items	31.00%

Schedule_of_Components_of_Net_

Schedule of Components of Net Periodic Benefit Cost (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Pension
Defined Benefit Plan Disclosure [Line Items]
Service cost	$6,290	$3,730
Interest cost	8,112	6,590
Expected return on assets	-9,104	-7,698
Prior service cost (credit)	105	111
Actuarial loss (gain)	3,108	1,202
Termination benefit charge	256
Net periodic benefit cost (credit)	8,767	3,935
Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	39	55
Interest cost	230	290
Prior service cost (credit)	-576	-814
Actuarial loss (gain)	-82	-35
Net periodic benefit cost (credit)	($389)	($504)

Commitments_and_Contingencies_

Commitments and Contingencies - Additional Information (Detail) (USD $)	3 Months Ended	12 Months Ended
	Mar. 31, 2015	Dec. 31, 2013	Dec. 31, 2014	Mar. 31, 2014
Commitments and Contingencies [Line Items]
Due from affiliate	$6,000,000		$6,000,000	$6,000,000
Percentage of employees represented in labor union	13.00%
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%
Revolving Line Of Credit Expires In July 2013
Commitments and Contingencies [Line Items]
Guarantee of affiliate's obligations	25,000,000
Loan Due May 2016
Commitments and Contingencies [Line Items]
Loan to affiliate		3,402,000
Due from affiliate			$1,808,000	$2,773,000

Business_Segments_Additional_I

Business Segments - Additional Information (Detail) (USD $)	3 Months Ended		12 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
	Segment
Segment Reporting Information [Line Items]
Reportable business segments	3
Total revenues	($691,347,000)	($428,629,000)
Reclassification of goodwill			600,000,000
Intersegment Eliminations
Segment Reporting Information [Line Items]
Total revenues	$18,377,000

Financial_Data_for_Continuing_

Financial Data for Continuing Operations for Corporations Reportable Business Segments (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Segment Reporting Information [Line Items]
Total revenues	$691,347,000	$428,629,000
Net Sales	631,876,000	379,678,000
Earnings (Loss) from operations	25,571,000	-15,898,000
Aggregates Business
Segment Reporting Information [Line Items]
Total revenues	526,083,000	366,315,000
Net Sales	476,557,000	322,330,000
Earnings (Loss) from operations	8,748,000	-15,796,000
Cement
Segment Reporting Information [Line Items]
Total revenues	102,100,000
Net Sales	96,565,000
Earnings (Loss) from operations	12,229,000
Magnesia Specialties
Segment Reporting Information [Line Items]
Total revenues	63,164,000	62,314,000
Net Sales	58,754,000	57,348,000
Earnings (Loss) from operations	17,789,000	16,285,000
Operating Segments
Segment Reporting Information [Line Items]
Total revenues	691,347,000	428,629,000
Net Sales	631,876,000	379,678,000
Earnings (Loss) from operations	25,571,000	-15,898,000
Operating Segments | Mid-America Group
Segment Reporting Information [Line Items]
Total revenues	140,834,000	115,708,000
Net Sales	129,705,000	106,533,000
Earnings (Loss) from operations	-4,203,000	-11,766,000
Operating Segments | Southeast Group
Segment Reporting Information [Line Items]
Total revenues	64,678,000	59,820,000
Net Sales	59,770,000	55,381,000
Earnings (Loss) from operations	-1,548,000	-6,111,000
Operating Segments | West Group
Segment Reporting Information [Line Items]
Total revenues	320,571,000	190,787,000
Net Sales	287,082,000	160,416,000
Earnings (Loss) from operations	14,499,000	2,081,000
Operating Segments | Corporate
Segment Reporting Information [Line Items]
Earnings (Loss) from operations	($13,195,000)	($16,387,000)

Asset_Employed_for_Continuing_

Asset Employed for Continuing Operations for Corporations Reportable Business Segments (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014
In Thousands, unless otherwise specified
Segment Reporting Asset Reconciling Item [Line Items]
Assets employed, Total	$7,417,646	$7,464,392	$3,255,257
Aggregates Business
Segment Reporting Asset Reconciling Item [Line Items]
Assets employed, Total	4,376,120	4,339,277	2,889,010
Cement
Segment Reporting Asset Reconciling Item [Line Items]
Assets employed, Total	2,422,119	2,451,799
Magnesia Specialties
Segment Reporting Asset Reconciling Item [Line Items]
Assets employed, Total	147,745	150,359	153,070
Operating Segments
Segment Reporting Asset Reconciling Item [Line Items]
Assets employed, Total	7,417,646	7,464,392	3,255,257
Operating Segments | Mid-America Group
Segment Reporting Asset Reconciling Item [Line Items]
Assets employed, Total	1,287,933	1,290,833	1,257,753
Operating Segments | Southeast Group
Segment Reporting Asset Reconciling Item [Line Items]
Assets employed, Total	597,461	604,044	607,219
Operating Segments | West Group
Segment Reporting Asset Reconciling Item [Line Items]
Assets employed, Total	2,490,726	2,444,400	1,024,038
Operating Segments | Corporate
Segment Reporting Asset Reconciling Item [Line Items]
Assets employed, Total	$471,662	$522,957	$213,177

Net_Sales_and_Gross_Profit_by_

Net Sales and Gross Profit by Line of Business (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Product Information [Line Items]
Net Sales	$631,876	$379,678
Gross profit (loss)	74,261	25,835
Operating Segments
Product Information [Line Items]
Net Sales	631,876	379,678
Operating Segments | Corporate
Product Information [Line Items]
Gross profit (loss)	-3,629	-507
Aggregates
Product Information [Line Items]
Net Sales	332,214	263,885
Gross profit (loss)	41,417	10,051
Asphalt
Product Information [Line Items]
Net Sales	9,645	10,498
Gross profit (loss)	-1,463	-1,426
Ready Mixed Concrete
Product Information [Line Items]
Net Sales	127,572	38,009
Gross profit (loss)	2,084	2,944
Road Paving
Product Information [Line Items]
Net Sales	7,126	9,938
Gross profit (loss)	-3,311	-3,982
Aggregates Business
Product Information [Line Items]
Net Sales	476,557	322,330
Gross profit (loss)	38,727	7,587
Cement
Product Information [Line Items]
Net Sales	96,565
Gross profit (loss)	18,985
Magnesia Specialties
Product Information [Line Items]
Net Sales	58,754	57,348
Gross profit (loss)	$20,178	$18,755

Components_of_Change_in_Other_

Components of Change in Other Assets and Liabilities Net (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Supplemental Cash Flow Elements [Abstract]
Other current and noncurrent assets	($4,083)	($783)
Accrued salaries, benefits and payroll taxes	-13,703	-3,984
Accrued insurance and other taxes	386	-1,838
Accrued income taxes	-46,700	-4,595
Accrued pension, postretirement and postemployment benefits	5,830	2,763
Other current and noncurrent liabilities	-10,827	9,311
Change in other assets and liabilities	($69,097)	$874

Supplemental_Cash_Flow_Informa2

Supplemental Cash Flow Information - Additional Information (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015
Supplemental Cash Flow Elements [Abstract]
Increase in income tax benefit	$23,300,000
Decrease in accrued interest expenses	4,403,000
Decrease in book overdraft	$5,724,000

Noncash_Investing_and_Financin

Noncash Investing and Financing Activities (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Supplemental Cash Flow Elements [Abstract]
Acquisition of assets through capital lease	$1,222	$5,930
Acquisition of assets through asset exchange	$5,153