Martin Marietta Materials (MLM) 10-Q 4 Aug 16 2016 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2016	Aug. 02, 2016
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2016
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	Q2
Trading Symbol	MLM
Entity Registrant Name	MARTIN MARIETTA MATERIALS INC
Entity Central Index Key	916,076
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		63,437,540

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015	Jun. 30, 2015
Current Assets:
Cash and cash equivalents	$ 28,596	$ 168,409	$ 44,169
Accounts receivable, net	534,459	410,921	497,468
Inventories, net	504,877	469,141	479,856
Assets held for sale			426,495
Other current assets	53,997	33,164	82,134
Total Current Assets	1,121,929	1,081,635	1,530,122
Property, plant and equipment	5,896,512	5,613,198	5,421,449
Allowances for depreciation, depletion and amortization	(2,574,307)	(2,457,198)	(2,371,926)
Net property, plant and equipment	3,322,205	3,156,000	3,049,523
Goodwill	2,136,783	2,068,235	2,065,882
Operating permits, net	442,349	444,725	447,702
Other intangibles, net	64,327	65,827	67,242
Other noncurrent assets	145,712	141,189	99,926
Total Assets	7,233,305	6,957,611	7,260,397
Current Liabilities:
Bank overdraft	7,143	10,235
Accounts payable	197,733	164,718	201,235
Accrued salaries, benefits and payroll taxes	24,864	30,939	27,590
Pension and postretirement benefits	9,120	8,168	8,133
Accrued insurance and other taxes	62,525	62,781	57,078
Current maturities of long-term debt and short-term facilities	238,155	18,713	15,433
Accrued interest	16,573	16,156	16,165
Other current liabilities	45,491	54,948	37,667
Total Current Liabilities	601,604	366,658	363,301
Long-term debt	1,541,062	1,550,061	1,637,905
Pension, postretirement and postemployment benefits	236,562	224,538	272,461
Deferred income taxes, net	639,776	583,459	521,932
Other noncurrent liabilities	197,801	172,718	154,365
Total Liabilities	3,216,805	2,897,434	2,949,964
Equity:
Common stock, par value $0.01 per share	633	643	668
Preferred stock, par value $0.01 per share
Additional paid-in capital	3,318,859	3,287,827	3,274,098
Accumulated other comprehensive loss	(106,068)	(105,622)	(112,814)
Retained earnings	800,028	874,436	1,146,821
Total Shareholders' Equity	4,013,452	4,057,284	4,308,773
Noncontrolling interests	3,048	2,893	1,660
Total Equity	4,016,500	4,060,177	4,310,433
Total Liabilities and Equity	$ 7,233,305	$ 6,957,611	$ 7,260,397

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Jun. 30, 2016	Dec. 31, 2015	Jun. 30, 2015
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 Earn

Consolidated Statements of Earnings and Comprehensive Earnings - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Income Statement [Abstract]
Net Sales	$ 915,436	$ 850,249	$ 1,649,396	$ 1,482,124
Freight and delivery revenues	61,862	71,170	116,636	130,641
Total revenues	977,298	921,419	1,766,032	1,612,765
Cost of sales	668,735	650,096	1,258,061	1,207,710
Freight and delivery costs	61,862	71,170	116,636	130,641
Total cost of revenues	730,597	721,266	1,374,697	1,338,351
Gross Profit	246,701	200,153	391,335	274,414
Selling, general & administrative expenses	61,509	56,783	121,370	106,233
Acquisition-related expenses, net	896	2,092	1,322	3,696
Other operating (income) and expenses, net	(3,446)	4,294	(2,869)	1,930
Earnings from Operations	187,742	136,984	271,512	162,555
Interest expense	20,294	19,087	40,328	38,418
Other nonoperating (income) and expenses, net	(8,100)	(3,011)	(9,130)	(2,118)
Earnings before taxes on income	175,548	120,908	240,314	126,255
Taxes on income	53,435	38,929	73,145	38,117
Consolidated net earnings	122,113	81,979	167,169	88,138
Less: Net earnings attributable to noncontrolling interests	61	41	122	73
Net Earnings Attributable to Martin Marietta Materials, Inc.	122,052	81,938	167,047	88,065
Consolidated Comprehensive Earnings: (See Note 1)
Earnings attributable to Martin Marietta Materials, Inc.	119,817	75,847	166,601	81,410
Earnings attributable to noncontrolling interests	63	43	155	78
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	$ 119,880	$ 75,890	$ 166,756	$ 81,488
Net Earnings Attributable to Martin Marietta Materials, Inc. Per Common Share:
Basic attributable to common shareholders	$ 1.91	$ 1.23	$ 2.61	$ 1.30
Diluted attributable to common shareholders	$ 1.90	$ 1.22	$ 2.60	$ 1.30
Weighted-Average Common Shares Outstanding:
Basic	63,532	67,373	63,845	67,392
Diluted	63,802	67,633	64,091	67,654
Cash Dividends Per Common Share	$ 0.40	$ 0.40	$ 0.80	$ 0.80

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Cash Flows from Operating Activities:
Consolidated net earnings	$ 167,169	$ 88,138
Adjustments to reconcile consolidated net earnings to net cash provided by operating activities:
Depreciation, depletion and amortization	139,617	134,958
Stock-based compensation expense	12,801	7,524
Gain on divestitures and sales of assets	(261)	(853)
Deferred income taxes	34,389	33,906
Excess tax benefits from stock-based compensation transactions	(3,948)	(55)
Other items, net	(5,767)	(341)
Changes in operating assets and liabilities, net of effects of acquisitions and divestitures:
Accounts receivable, net	(117,524)	(76,061)
Inventories, net	(33,131)	(27,661)
Accounts payable	32,521	(3,416)
Other assets and liabilities, net	(22,495)	(29,070)
Net Cash Provided by Operating Activities	203,371	127,069
Cash Flows from Investing Activities:
Additions to property, plant and equipment	(210,559)	(127,990)
Acquisitions, net	(123,000)	(10,713)
Cash received in acquisition	3,446
Proceeds from divestitures and sales of assets	4,474	1,972
Repayments from affiliate		1,808
Payment of railcar construction advances		(25,234)
Reimbursement of railcar construction advances		25,234
Net Cash Used for Investing Activities	(325,639)	(134,923)
Cash Flows from Financing Activities:
Borrowings of debt	280,000	80,000
Repayments of debt	(70,420)	(8,144)
Payments on capital lease obligations	(1,563)	(1,831)
Change in bank overdraft	(3,092)	(183)
Dividends paid	(51,467)	(54,285)
Issuances of common stock	15,049	27,760
Repurchases of common stock	(190,000)	(100,000)
Excess tax benefits from stock-based compensation transactions	3,948	55
Net Cash Used for Financing Activities	(17,545)	(56,628)
Net Decrease in Cash and Cash Equivalents	(139,813)	(64,482)
Cash and Cash Equivalents, beginning of period	168,409	108,651
Cash and Cash Equivalents, end of period	28,596	44,169
Supplemental Disclosures of Cash Flow Information:
Cash paid for interest	36,630	35,447
Cash paid for income taxes	$ 47,159	$ 24,334

Consolidated Statement of Total

Consolidated Statement of Total Equity - 6 months ended Jun. 30, 2016 - 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, 2015	$ 4,060,177	$ 643	$ 3,287,827	$ (105,622)	$ 874,436	$ 4,057,284	$ 2,893
Beginning Balance (in shares) at Dec. 31, 2015		64,479,000
Consolidated net earnings	167,169				167,047	167,047	122
Other comprehensive earnings, net of tax	(413)			(446)		(446)	33
Dividends declared	(51,467)				(51,467)	(51,467)
Issuances of common stock for stock award plans	18,233	$ 2	18,231			18,233
Issuances of common stock for stock award plans (in shares)		197,000
Repurchases of common stock	(190,000)	$ (12)			(189,988)	(190,000)
Repurchases of common stock, Shares		(1,244,000)
Stock-based compensation expense	12,801		12,801			12,801
Ending Balance at Jun. 30, 2016	$ 4,016,500	$ 633	$ 3,318,859	$ (106,068)	$ 800,028	$ 4,013,452	$ 3,048
Ending Balance (in shares) at Jun. 30, 2016		63,432,000

Significant Accounting Policies

Significant Accounting Policies	6 Months Ended
	Jun. 30, 2016
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 56% of consolidated net sales for the six months ended June 30, 2016 (55% of full-year 2015 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 29% of consolidated net sales for the six months ended June 30, 2016 (27% of full-year 2015 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 in 26 states, Nova Scotia and the Bahamas. 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, Tennessee, Arkansas, Colorado, southern Kansas, Louisiana, western Nebraska, Nevada, Oklahoma, Texas, Utah and Wyoming The Corporation has a Cement segment, which accounted for 8% of consolidated net sales for the six months ended June 30, 2016 (11% of full-year 2015 consolidated net sales). The Cement segment has production facilities located in Midlothian, Texas, south of Dallas-Fort Worth and Hunter, Texas, north of San Antonio. The Cement business produces Portland and specialty 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 owned by the Cement business and are adjacent to each of the plants. The Corporation has a Magnesia Specialties segment with manufacturing facilities in Manistee, Michigan, and Woodville, Ohio. The Magnesia Specialties segment, which accounted for 7% of consolidated net sales for the six months ended June 30, 2016 (7% of full-year 2015 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, 2015. In the opinion of management, the interim consolidated financial information provided herein reflects all adjustments, consisting of normal recurring accruals, necessary for a fair statement of the results of operations, financial position and cash flows for the interim periods. The consolidated results of operations for the six months ended June 30, 2016 are not indicative of the results expected for other interim periods or the full year. The consolidated balance sheet at December 31, 2015 has been derived from the audited consolidated financial statements at that date but does not include all disclosures required by accounting principles generally accepted in the United States. 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, 2015. Debt Issuance Costs The Financial Accounting Standards Board (“FASB”) issued Accounting Standard Update (“ASU”) 2015-03, “Simplifying the Presentation of Debt Issuance Costs” Other noncurrent assets Long-term debt Other current assets Current maturities of long-term debt and short-term maturities 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 January 1, 2018 and can be applied on a full retrospective or modified retrospective approach. The Corporation will not early adopt this standard. The Corporation is currently evaluating the impact the provisions of the new standard will have on its financial statements and expects to complete its evaluation by the end of 2016. 1. Significant Accounting Policies (continued) Lease Standard In February 2016, the FASB issued a new accounting standard, Accounting Standards Update 2016-2 – Leases, Share-based Payment Standard In March 2016, the FASB issued ASU 2016-09, Compensation—Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting 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, 2016 2015 2016 2015 (Dollars in Thousands) Net earnings attributable to Martin Marietta Materials, Inc. $ 122,052 $ 81,938 $ 167,047 $ 88,065 Other comprehensive loss, net of tax (2,235 ) (6,091 ) (446 ) (6,655 ) Comprehensive earnings attributable to Martin Marietta Materials, Inc. $ 119,817 $ 75,847 $ 166,601 $ 81,410 1. Significant Accounting Policies (continued) Consolidated Comprehensive Earnings/Loss and Accumulated Other Comprehensive Loss (continued) Comprehensive earnings attributable to noncontrolling interests, consisting of net earnings 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, 2016 2015 2016 2015 (Dollars in Thousands) Net earnings attributable to noncontrolling interests $ 61 $ 41 $ 122 $ 73 Other comprehensive earnings, net of tax 2 2 33 5 Comprehensive earnings attributable to noncontrolling interests $ 63 $ 43 $ 155 $ 78 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) earnings, 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, 2016 Balance at beginning of period $ (101,907 ) $ (149 ) $ (1,777 ) $ (103,833 ) Other comprehensive loss before reclassifications, net of tax (3,736 ) (232 ) — (3,968 ) Amounts reclassified from accumulated other comprehensive earnings, net of tax 1,529 — 204 1,733 Other comprehensive (loss) earnings, net of tax (2,207 ) (232 ) 204 (2,235 ) Balance at end of period $ (104,114 ) $ (381 ) $ (1,573 ) $ (106,068 ) 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 earnings, 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 ) 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 of $2,346,000 and $6,793,000 for the three months ended June 30, 2016 and 2015, 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, 2016 Balance at beginning of period $ (103,380 ) $ (264 ) $ (1,978 ) $ (105,622 ) Other comprehensive loss before reclassifications, net of tax (3,830 ) (117 ) — (3,947 ) Amounts reclassified from accumulated other comprehensive earnings, net of tax 3,096 — 405 3,501 Other comprehensive (loss) earnings, net of tax (734 ) (117 ) 405 (446 ) Balance at end of period $ (104,114 ) $ (381 ) $ (1,573 ) $ (106,068 ) 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 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 ) The other comprehensive loss before reclassifications for pension and postretirement benefit plans is net of tax of $2,405,000 and $6,904,000 for the six months ended June 30, 2016 and 2015, 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, 2016 Balance at beginning of period $ 65,523 $ 1,159 $ 66,682 Tax effect of other comprehensive earnings 1,408 (136 ) 1,272 Balance at end of period $ 66,931 $ 1,023 $ 67,954 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 Six Months Ended June 30, 2016 Balance at beginning of period $ 66,467 $ 1,290 $ 67,757 Tax effect of other comprehensive earnings 464 (267 ) 197 Balance at end of period $ 66,931 $ 1,023 $ 67,954 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 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 2016 2015 2016 2015 comprehensive earnings (Dollars in Thousands) Pension and postretirement benefit plans Settlement charge $ — $ — $ 59 $ — Amortization of: Prior service credit (518 ) (469 ) $ (806 ) $ (939 ) Actuarial loss 3,007 7,274 5,787 10,546 2,489 6,805 5,040 9,607 Cost of sales; Selling, general and administrative expenses Tax benefit (960 ) (2,647 ) (1,944 ) (3,737 ) Taxes on income $ 1,529 $ 4,158 $ 3,096 $ 5,870 Unamortized value of terminated forward starting interest rate swap Additional interest expense $ 340 $ 317 $ 672 $ 624 Interest expense Tax benefit (136 ) (125 ) (267 ) (245 ) Taxes on income $ 204 $ 192 $ 405 $ 379 1. Significant Accounting Policies (continued) Earnings per Common Share The numerator for basic and diluted earnings per common share is net earnings attributable to Martin Marietta Materials, Inc. reduced by dividends and undistributed earnings attributable to certain of the Corporation’s stock-based compensation. 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, 2016 and 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. 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, 2016 2015 2016 2015 (In Thousands) Net earnings from continuing operations attributable to Martin Marietta Materials, Inc. $ 122,052 $ 81,938 $ 167,047 $ 88,065 Less: Distributed and undistributed earnings attributable to unvested awards 519 (876 ) 730 403 Basic and diluted net earnings available to common shareholders attributable to Martin Marietta Materials, Inc. $ 121,533 $ 82,814 $ 166,317 $ 87,662 Basic weighted-average common shares outstanding 63,532 67,373 63,845 67,392 Effect of dilutive employee and director awards 270 260 246 262 Diluted weighted-average common shares outstanding 63,802 67,633 64,091 67,654 Page 1 of 61

Inventories, Net

Inventories, Net	6 Months Ended
	Jun. 30, 2016
Inventory Disclosure [Abstract]
Inventories, Net	2. Inventories, Net June 30, December 31, June 30, 2016 2015 2015 (Dollars in Thousands) Finished products $ 463,807 $ 433,649 $ 425,732 Products in process and raw materials 60,324 55,194 62,059 Supplies and expendable parts 113,110 110,882 112,592 637,241 599,725 600,383 Less: Allowances (132,364 ) (130,584 ) (120,527 ) Total $ 504,877 $ 469,141 $ 479,856

Long-Term Debt

Long-Term Debt	6 Months Ended
	Jun. 30, 2016
Debt Disclosure [Abstract]
Long-Term Debt	3. Long-Term Debt June 30, December 31, June 30, 2016 2015 2015 (Dollars in Thousands) 6.6% Senior Notes, due 2018 $ 299,294 $ 299,113 $ 298,931 7% Debentures, due 2025 124,046 124,002 123,960 6.25% Senior Notes, due 2037 227,947 227,917 227,898 4.25 % Senior Notes, due 2024 394,977 394,690 394,441 Floating Rate Notes, due 2017, interest rate of 1.73%, 1.71% and 1.38% at June 30, 2016, December 31, 2015 and June 30, 2015, respectively 298,793 298,868 298,514 Term Loan Facility, due 2018, interest rate of 1.96%, 1.86% and 1.69% at June 30, 2016, December 31, 2015 and June 30, 2015, respectively 213,571 222,521 228,346 Trade Receivable Facility, interest rate of 1.16% and 0.88% at June 30, 2016 and June 30, 2015, respectively 220,000 — 80,000 Other notes 589 1,663 1,248 Total debt 1,779,217 1,568,774 1,653,338 Less: Current maturities (238,155 ) (18,713 ) (15,433 ) Long-term debt $ 1,541,062 $ 1,550,061 $ 1,637,905 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. Management intends to renew the Trade Receivable Facility beyond 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, and is limited to the lesser of the facility limit or the borrowing base, as defined, of $391,600,000, $282,258,000 and $450,791,000 at June 30, 2016, December 31, 2015 and June 30, 2015, respectively. These receivables are originated by the Corporation and then sold to the wholly-owned special-purpose subsidiary by the Corporation. The Corporation con subsidiary The Trade Receivable Facility contains a cross-default provision to the Corporation’s other debt agreements. 3. 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 accordance with the amended Credit Agreement, the Corporation adjusted consolidated EBITDA to add back 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. The Corporation was in compliance with this Ratio at June 30, 2016. 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, 2016, December 31, 2015 and June 30, 2015, the Corporation had $2,507,000 of outstanding letters of credit issued under the Revolving Facility. Current debt maturities consist of borrowings under the Trade Receivable Facility as well as the current portions of the Term Loan Facility and other notes. The increase in current debt maturities as of June 30, 2016 is attributable to the balance drawn on the Trade Receivable Facility. The Floating Rate Notes have been classified as a noncurrent liability as the Corporation has the intent and ability to refinance on a long-term basis before or at its maturity of June 30, 2017. 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, 2016, the Corporation recognized $340,000 and $672,000, respectively, as additional interest expense. For the three and six months ended June 30, 2015, the Corporation recognized $317,000 and $624,000, 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 $1,400,000 until the maturity of the 6.6% Senior Notes in 2018.

Financial Instruments

Financial Instruments	6 Months Ended
	Jun. 30, 2016
Financial Instruments Disclosure [Abstract]
Financial Instruments	4. 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 original 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. 4. 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 classified in the line items Other current assets Other noncurrent assets 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 $1,779,217,000 and $1,890,319,000, respectively, at June 30, 2016; $1,568,774,000 and $1,625,193,000, respectively, at December 31, 2015; and $1,653,338,000 and $1,729,511,000, respectively, at June 30, 2015. 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 estimated fair value of other borrowings, which primarily represents variable-rate debt, was based on Level 2 of the fair value hierarchy using quoted market prices for similar debt instruments, and approximates their carrying amounts as the interest rates reset periodically.

Income Taxes

Income Taxes	6 Months Ended
	Jun. 30, 2016
Income Tax Disclosure [Abstract]
Income Taxes	5. Income Taxes The Corporation’s effective income tax rates for the six months ended June 30, 2016 and 2015 were 30.4% and 30.2%, respectively. The estimated effective income tax rates reflect 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 Corporation records interest accrued in relation to unrecognized tax benefits as income tax expense. Penalties, if incurred, are recorded as other expenses in the consolidated statements of earnings and comprehensive earnings.

Pension and Postretirement Bene

Pension and Postretirement Benefits	6 Months Ended
	Jun. 30, 2016
Compensation And Retirement Disclosure [Abstract]
Pension and Postretirement Benefits	6. 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 2016 2015 2016 2015 (Dollars in Thousands) Service cost $ 5,776 $ 5,513 $ 24 $ 34 Interest cost 9,331 8,213 259 229 Expected return on assets (9,822 ) (8,887 ) — — Amortization of: Prior service cost (credit) 91 101 (609 ) (570 ) Actuarial loss (gain) 3,146 7,351 (139 ) (77 ) Special termination benefit 638 1,206 (8 ) — Net periodic benefit cost (credit) $ 9,160 $ 13,497 $ (473 ) $ (384 ) Six Months Ended June 30, Pension Postretirement Benefits 2016 2015 2016 2015 (Dollars in Thousands) Service cost $ 11,082 $ 11,505 $ 43 $ 68 Interest cost 17,938 16,575 432 464 Expected return on assets (18,848 ) (18,190 ) — — Amortization of: Prior service cost (credit) 175 211 (981 ) (1,150 ) Actuarial loss (gain) 6,036 10,700 (249 ) (154 ) Settlement charge 59 — — — Special termination benefit 764 1,462 (8 ) — Net periodic benefit cost (credit) $ 17,206 $ 22,263 $ (763 ) $ (772 ) The Corporation currently estimates that it will contribute $38,752,000 to its pension and SERP plans in 2016.

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 30, 2016
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	7 . 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 addition, the Corporation has a $6,000,000 outstanding loan due from this unconsolidated affiliate as of June 30, 2016, December 31, 2015 and June 30, 2015. Employees Approximately 10% 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 Magnesia Specialties segments. 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

Business Segments	6 Months Ended
	Jun. 30, 2016
Segment Reporting [Abstract]
Business Segments	8 . 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. 8. 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, exclude intersegment sales, which are eliminated. Three Months Ended Six Months Ended June 30, June 30, 2016 2015 2016 2015 (Dollars in Thousands) Total revenues Mid-America Group $ 278,676 $ 257,649 $ 465,023 $ 398,482 Southeast Group 87,600 81,518 159,271 146,195 West Group 484,918 411,235 877,913 731,807 Total Aggregates Business 851,194 750,402 1,502,207 1,276,484 Cement 62,468 105,899 136,019 207,999 Magnesia Specialties 63,636 65,118 127,806 128,282 Total $ 977,298 $ 921,419 $ 1,766,032 $ 1,612,765 Net sales Mid-America Group $ 258,988 $ 237,415 $ 432,360 $ 367,120 Southeast Group 82,676 76,483 149,961 136,253 West Group 455,115 375,489 819,040 662,570 Total Aggregates Business 796,779 689,387 1,401,361 1,165,943 Cement 59,791 100,405 129,664 196,970 Magnesia Specialties 58,866 60,457 118,371 119,211 Total $ 915,436 $ 850,249 $ 1,649,396 $ 1,482,124 Earnings (Loss) from operations Mid-America Group $ 80,552 $ 66,894 $ 94,976 $ 62,691 Southeast Group 11,548 4,818 18,519 3,269 West Group 77,404 49,177 116,201 63,676 Total Aggregates Business 169,504 120,889 229,696 129,636 Cement 21,309 22,468 47,626 34,697 Magnesia Specialties 19,227 18,751 39,791 36,541 Corporate (22,298 ) (25,124 ) (45,601 ) (38,319 ) Total $ 187,742 $ 136,984 $ 271,512 $ 162,555 8. Business Segments (continued) The decline in the Cement business’s total and net sales is primarily attributable to the California cement operations, included in the three and six months ended June 30, 2015 and divested as of September 30, 2015. For the three months ended June 30, 2015, total revenues, net sales and loss from operations for the California cement operations were $35,318,000, $34,160,000 and $485,000, respectively. For the six months ended June 30, 2015, total revenues, net sales and loss from operations for the California cement operations were $69,674,000, $67,267,000 and $7,906,000, respectively. Cement intersegment sales, which are to the aggregates and ready mixed concrete product lines in the West Group, were $27,649,000 and $54,637,000 for the three and six months ended June 30, 2016, respectively, and $20,854,000 and $38,955,000 for the three and six months ended June 30, 2015, respectively. The Aggregates business includes the aggregates product line and aggregates-related downstream product lines, which include asphalt, ready mixed concrete and road paving products. 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, 2016 2015 2016 2015 (Dollars in Thousands) Net sales Aggregates $ 516,283 $ 481,616 $ 922,721 $ 813,830 Asphalt and Paving 65,609 58,021 76,967 74,790 Ready Mixed Concrete 214,887 149,750 401,673 277,323 Total Aggregates Business 796,779 689,387 1,401,361 1,165,943 Cement 59,791 100,405 129,664 196,970 Magnesia Specialties 58,866 60,457 118,371 119,211 Total $ 915,436 $ 850,249 $ 1,649,396 $ 1,482,124 Gross profit (loss) Aggregates $ 164,353 $ 137,272 $ 245,431 $ 178,690 Asphalt and Paving 12,876 7,891 6,714 3,116 Ready Mixed Concrete 25,293 9,341 43,380 11,424 Total Aggregates Business 202,522 154,504 295,525 193,230 Cement 24,002 30,414 56,559 49,400 Magnesia Specialties 21,692 21,224 44,662 41,402 Corporate (1,515 ) (5,989 ) (5,411 ) (9,618 ) Total $ 246,701 $ 200,153 $ 391,335 $ 274,414 For the three months ended June 30, 2015, gross profit for the California cement operations was $3,424,000. For the six months ended June 30, 2015, the operation’s gross loss was $647,000.

Supplemental Cash Flow Informat

Supplemental Cash Flow Information	6 Months Ended
	Jun. 30, 2016
Supplemental Cash Flow Elements [Abstract]
Supplemental Cash Flow Information	9 . Supplemental Cash Flow Information The components of the change in other assets and liabilities, net, are as follows: Six Months Ended June 30, 2016 2015 (Dollars in Thousands) Other current and noncurrent assets $ (9,691 ) $ (5,501 ) Accrued salaries, benefits and payroll taxes (7,808 ) (13,794 ) Accrued insurance and other taxes (256 ) (1,278 ) Accrued income taxes (8,495 ) (19,902 ) Accrued pension, postretirement and postemployment benefits 11,757 16,283 Other current and noncurrent liabilities (8,002 ) (4,878 ) $ (22,495 ) $ (29,070 ) The change in accrued salaries, benefits and payroll taxes in 2016 compared to 2015 was primarily attributable to TXI-related severance payments made in 2015. The change in accrued income taxes was attributable to higher taxable income in 2016 compared to 2015. Noncash investing and financing activities are as follows: Six Months Ended June 30, 2016 2015 (Dollars in Thousands) Noncash investing and financing activities: Acquisition of assets through capital lease $ — $ 1,331 Acquisition of assets through asset exchange — 5,000

Business Combination

Business Combination	6 Months Ended
	Jun. 30, 2016
Business Combinations [Abstract]
Business Combination	10. Business Combination During the first quarter 2016, the Corporation acquired the outstanding stock of Rocky Mountain Materials and Asphalt, Inc., and Rocky Mountain Premix Inc. The acquisition provides more than 500 million tons of mineral reserves and expands the Corporation’s presence along the Front Range of the Rocky Mountains, home to 80% of Colorado’s population. The acquired operations are reported through the West Group. The Corporation has recorded preliminary fair values of the assets acquired and liabilities assumed; however, certain amounts are subject to change as additional reviews are performed, including asset and liability verification and review of seller’s final tax return. Specific accounts subject to ongoing purchase accounting include property, plant and equipment; goodwill; accrued expenses and deferred income taxes. The acquisition was not financially material; therefore, pro forma information is not required.

Stock-Based Compensation

Stock-Based Compensation	6 Months Ended
	Jun. 30, 2016
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock-Based Compensation	11. Stock-Based Compensation During the quarter ended March 31, 2016, the Corporation awarded its annual grant of stock-based compensation, which included 75,421 of performance stock units and 68,720 of restricted stock units. The grant-date fair value of each award is $142.02 for the performance stock units and $124.41 for the restricted stock units. No stock options are expected to be awarded in 2016. In past years, annual stock-based compensation awards were primarily made in the second quarter of the year. The change in the composition of the awards and the timing of the annual grant resulted in higher expense recorded in the first half of the year compared with prior years. For the six months ended June 30, 2016 and 2015, stock-based compensation expense was $12,801,000 and $7,524,000, respectively.

Significant Accounting Polici18

Significant Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2016
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 56% of consolidated net sales for the six months ended June 30, 2016 (55% of full-year 2015 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 29% of consolidated net sales for the six months ended June 30, 2016 (27% of full-year 2015 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 in 26 states, Nova Scotia and the Bahamas. 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, Tennessee, Arkansas, Colorado, southern Kansas, Louisiana, western Nebraska, Nevada, Oklahoma, Texas, Utah and Wyoming The Corporation has a Cement segment, which accounted for 8% of consolidated net sales for the six months ended June 30, 2016 (11% of full-year 2015 consolidated net sales). The Cement segment has production facilities located in Midlothian, Texas, south of Dallas-Fort Worth and Hunter, Texas, north of San Antonio. The Cement business produces Portland and specialty 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 owned by the Cement business and are adjacent to each of the plants. The Corporation has a Magnesia Specialties segment with manufacturing facilities in Manistee, Michigan, and Woodville, Ohio. The Magnesia Specialties segment, which accounted for 7% of consolidated net sales for the six months ended June 30, 2016 (7% of full-year 2015 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. Page 1 of 61
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, 2015. In the opinion of management, the interim consolidated financial information provided herein reflects all adjustments, consisting of normal recurring accruals, necessary for a fair statement of the results of operations, financial position and cash flows for the interim periods. The consolidated results of operations for the six months ended June 30, 2016 are not indicative of the results expected for other interim periods or the full year. The consolidated balance sheet at December 31, 2015 has been derived from the audited consolidated financial statements at that date but does not include all disclosures required by accounting principles generally accepted in the United States. 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, 2015.
Debt Issuance Cost, Revenue Recognition Standard, Lease Standard and Share-based Payment Standard	Debt Issuance Costs The Financial Accounting Standards Board (“FASB”) issued Accounting Standard Update (“ASU”) 2015-03, “Simplifying the Presentation of Debt Issuance Costs” Other noncurrent assets Long-term debt Other current assets Current maturities of long-term debt and short-term maturities 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 January 1, 2018 and can be applied on a full retrospective or modified retrospective approach. The Corporation will not early adopt this standard. The Corporation is currently evaluating the impact the provisions of the new standard will have on its financial statements and expects to complete its evaluation by the end of 2016. 1. Significant Accounting Policies (continued) Lease Standard In February 2016, the FASB issued a new accounting standard, Accounting Standards Update 2016-2 – Leases, Share-based Payment Standard In March 2016, the FASB issued ASU 2016-09, Compensation—Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting
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 Six Months Ended June 30, June 30, 2016 2015 2016 2015 (Dollars in Thousands) Net earnings attributable to Martin Marietta Materials, Inc. $ 122,052 $ 81,938 $ 167,047 $ 88,065 Other comprehensive loss, net of tax (2,235 ) (6,091 ) (446 ) (6,655 ) Comprehensive earnings attributable to Martin Marietta Materials, Inc. $ 119,817 $ 75,847 $ 166,601 $ 81,410 1. Significant Accounting Policies (continued) Consolidated Comprehensive Earnings/Loss and Accumulated Other Comprehensive Loss (continued) Comprehensive earnings attributable to noncontrolling interests, consisting of net earnings 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, 2016 2015 2016 2015 (Dollars in Thousands) Net earnings attributable to noncontrolling interests $ 61 $ 41 $ 122 $ 73 Other comprehensive earnings, net of tax 2 2 33 5 Comprehensive earnings attributable to noncontrolling interests $ 63 $ 43 $ 155 $ 78 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) earnings, 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, 2016 Balance at beginning of period $ (101,907 ) $ (149 ) $ (1,777 ) $ (103,833 ) Other comprehensive loss before reclassifications, net of tax (3,736 ) (232 ) — (3,968 ) Amounts reclassified from accumulated other comprehensive earnings, net of tax 1,529 — 204 1,733 Other comprehensive (loss) earnings, net of tax (2,207 ) (232 ) 204 (2,235 ) Balance at end of period $ (104,114 ) $ (381 ) $ (1,573 ) $ (106,068 ) 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 earnings, 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 ) 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 of $2,346,000 and $6,793,000 for the three months ended June 30, 2016 and 2015, 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, 2016 Balance at beginning of period $ (103,380 ) $ (264 ) $ (1,978 ) $ (105,622 ) Other comprehensive loss before reclassifications, net of tax (3,830 ) (117 ) — (3,947 ) Amounts reclassified from accumulated other comprehensive earnings, net of tax 3,096 — 405 3,501 Other comprehensive (loss) earnings, net of tax (734 ) (117 ) 405 (446 ) Balance at end of period $ (104,114 ) $ (381 ) $ (1,573 ) $ (106,068 ) 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 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 ) The other comprehensive loss before reclassifications for pension and postretirement benefit plans is net of tax of $2,405,000 and $6,904,000 for the six months ended June 30, 2016 and 2015, 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, 2016 Balance at beginning of period $ 65,523 $ 1,159 $ 66,682 Tax effect of other comprehensive earnings 1,408 (136 ) 1,272 Balance at end of period $ 66,931 $ 1,023 $ 67,954 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 Six Months Ended June 30, 2016 Balance at beginning of period $ 66,467 $ 1,290 $ 67,757 Tax effect of other comprehensive earnings 464 (267 ) 197 Balance at end of period $ 66,931 $ 1,023 $ 67,954 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 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 2016 2015 2016 2015 comprehensive earnings (Dollars in Thousands) Pension and postretirement benefit plans Settlement charge $ — $ — $ 59 $ — Amortization of: Prior service credit (518 ) (469 ) $ (806 ) $ (939 ) Actuarial loss 3,007 7,274 5,787 10,546 2,489 6,805 5,040 9,607 Cost of sales; Selling, general and administrative expenses Tax benefit (960 ) (2,647 ) (1,944 ) (3,737 ) Taxes on income $ 1,529 $ 4,158 $ 3,096 $ 5,870 Unamortized value of terminated forward starting interest rate swap Additional interest expense $ 340 $ 317 $ 672 $ 624 Interest expense Tax benefit (136 ) (125 ) (267 ) (245 ) Taxes on income $ 204 $ 192 $ 405 $ 379
Earnings (Loss) per Common Share	1. Significant Accounting Policies (continued) Earnings per Common Share The numerator for basic and diluted earnings per common share is net earnings attributable to Martin Marietta Materials, Inc. reduced by dividends and undistributed earnings attributable to certain of the Corporation’s stock-based compensation. 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, 2016 and 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. 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, 2016 2015 2016 2015 (In Thousands) Net earnings from continuing operations attributable to Martin Marietta Materials, Inc. $ 122,052 $ 81,938 $ 167,047 $ 88,065 Less: Distributed and undistributed earnings attributable to unvested awards 519 (876 ) 730 403 Basic and diluted net earnings available to common shareholders attributable to Martin Marietta Materials, Inc. $ 121,533 $ 82,814 $ 166,317 $ 87,662 Basic weighted-average common shares outstanding 63,532 67,373 63,845 67,392 Effect of dilutive employee and director awards 270 260 246 262 Diluted weighted-average common shares outstanding 63,802 67,633 64,091 67,654

Significant Accounting Polici19

Significant Accounting Policies (Tables)	6 Months Ended
	Jun. 30, 2016
Significant Accounting Policies [Line Items]
Changes in Accumulated Other Comprehensive (Loss) Earnings, Net of Tax	Changes in accumulated other comprehensive (loss) earnings, 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, 2016 Balance at beginning of period $ (101,907 ) $ (149 ) $ (1,777 ) $ (103,833 ) Other comprehensive loss before reclassifications, net of tax (3,736 ) (232 ) — (3,968 ) Amounts reclassified from accumulated other comprehensive earnings, net of tax 1,529 — 204 1,733 Other comprehensive (loss) earnings, net of tax (2,207 ) (232 ) 204 (2,235 ) Balance at end of period $ (104,114 ) $ (381 ) $ (1,573 ) $ (106,068 ) 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 earnings, 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 ) (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, 2016 Balance at beginning of period $ (103,380 ) $ (264 ) $ (1,978 ) $ (105,622 ) Other comprehensive loss before reclassifications, net of tax (3,830 ) (117 ) — (3,947 ) Amounts reclassified from accumulated other comprehensive earnings, net of tax 3,096 — 405 3,501 Other comprehensive (loss) earnings, net of tax (734 ) (117 ) 405 (446 ) Balance at end of period $ (104,114 ) $ (381 ) $ (1,573 ) $ (106,068 ) 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 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 )
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, 2016 Balance at beginning of period $ 65,523 $ 1,159 $ 66,682 Tax effect of other comprehensive earnings 1,408 (136 ) 1,272 Balance at end of period $ 66,931 $ 1,023 $ 67,954 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 Six Months Ended June 30, 2016 Balance at beginning of period $ 66,467 $ 1,290 $ 67,757 Tax effect of other comprehensive earnings 464 (267 ) 197 Balance at end of period $ 66,931 $ 1,023 $ 67,954 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
Reclassification Out of Accumulated Other Comprehensive Loss	Reclassifications out of accumulated other comprehensive loss are as follows: Three Months Ended Six Months Ended Affected line items in the consolidated June 30, June 30, statements of earnings and 2016 2015 2016 2015 comprehensive earnings (Dollars in Thousands) Pension and postretirement benefit plans Settlement charge $ — $ — $ 59 $ — Amortization of: Prior service credit (518 ) (469 ) $ (806 ) $ (939 ) Actuarial loss 3,007 7,274 5,787 10,546 2,489 6,805 5,040 9,607 Cost of sales; Selling, general and administrative expenses Tax benefit (960 ) (2,647 ) (1,944 ) (3,737 ) Taxes on income $ 1,529 $ 4,158 $ 3,096 $ 5,870 Unamortized value of terminated forward starting interest rate swap Additional interest expense $ 340 $ 317 $ 672 $ 624 Interest expense Tax benefit (136 ) (125 ) (267 ) (245 ) Taxes on income $ 204 $ 192 $ 405 $ 379
Basic and Diluted Earnings (Loss) per Common Share	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, 2016 2015 2016 2015 (In Thousands) Net earnings from continuing operations attributable to Martin Marietta Materials, Inc. $ 122,052 $ 81,938 $ 167,047 $ 88,065 Less: Distributed and undistributed earnings attributable to unvested awards 519 (876 ) 730 403 Basic and diluted net earnings available to common shareholders attributable to Martin Marietta Materials, Inc. $ 121,533 $ 82,814 $ 166,317 $ 87,662 Basic weighted-average common shares outstanding 63,532 67,373 63,845 67,392 Effect of dilutive employee and director awards 270 260 246 262 Diluted weighted-average common shares outstanding 63,802 67,633 64,091 67,654
Parent
Significant Accounting Policies [Line Items]
Comprehensive Earnings	Comprehensive earnings attributable to Martin Marietta is as follows: Three Months Ended Six Months Ended June 30, June 30, 2016 2015 2016 2015 (Dollars in Thousands) Net earnings attributable to Martin Marietta Materials, Inc. $ 122,052 $ 81,938 $ 167,047 $ 88,065 Other comprehensive loss, net of tax (2,235 ) (6,091 ) (446 ) (6,655 ) Comprehensive earnings attributable to Martin Marietta Materials, Inc. $ 119,817 $ 75,847 $ 166,601 $ 81,410
Noncontrolling Interests
Significant Accounting Policies [Line Items]
Comprehensive Earnings	1. Significant Accounting Policies (continued) Consolidated Comprehensive Earnings/Loss and Accumulated Other Comprehensive Loss (continued) Comprehensive earnings attributable to noncontrolling interests, consisting of net earnings 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, 2016 2015 2016 2015 (Dollars in Thousands) Net earnings attributable to noncontrolling interests $ 61 $ 41 $ 122 $ 73 Other comprehensive earnings, net of tax 2 2 33 5 Comprehensive earnings attributable to noncontrolling interests $ 63 $ 43 $ 155 $ 78

Inventories, Net (Tables)

Inventories, Net (Tables)	6 Months Ended
	Jun. 30, 2016
Inventory Disclosure [Abstract]
Schedule of Inventories Net	June 30, December 31, June 30, 2016 2015 2015 (Dollars in Thousands) Finished products $ 463,807 $ 433,649 $ 425,732 Products in process and raw materials 60,324 55,194 62,059 Supplies and expendable parts 113,110 110,882 112,592 637,241 599,725 600,383 Less: Allowances (132,364 ) (130,584 ) (120,527 ) Total $ 504,877 $ 469,141 $ 479,856

Long-Term Debt (Tables)

Long-Term Debt (Tables)	6 Months Ended
	Jun. 30, 2016
Debt Disclosure [Abstract]
Long-Term Debt	June 30, December 31, June 30, 2016 2015 2015 (Dollars in Thousands) 6.6% Senior Notes, due 2018 $ 299,294 $ 299,113 $ 298,931 7% Debentures, due 2025 124,046 124,002 123,960 6.25% Senior Notes, due 2037 227,947 227,917 227,898 4.25 % Senior Notes, due 2024 394,977 394,690 394,441 Floating Rate Notes, due 2017, interest rate of 1.73%, 1.71% and 1.38% at June 30, 2016, December 31, 2015 and June 30, 2015, respectively 298,793 298,868 298,514 Term Loan Facility, due 2018, interest rate of 1.96%, 1.86% and 1.69% at June 30, 2016, December 31, 2015 and June 30, 2015, respectively 213,571 222,521 228,346 Trade Receivable Facility, interest rate of 1.16% and 0.88% at June 30, 2016 and June 30, 2015, respectively 220,000 — 80,000 Other notes 589 1,663 1,248 Total debt 1,779,217 1,568,774 1,653,338 Less: Current maturities (238,155 ) (18,713 ) (15,433 ) Long-term debt $ 1,541,062 $ 1,550,061 $ 1,637,905

Pension and Postretirement Be22

Pension and Postretirement Benefits (Tables)	6 Months Ended
	Jun. 30, 2016
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 2016 2015 2016 2015 (Dollars in Thousands) Service cost $ 5,776 $ 5,513 $ 24 $ 34 Interest cost 9,331 8,213 259 229 Expected return on assets (9,822 ) (8,887 ) — — Amortization of: Prior service cost (credit) 91 101 (609 ) (570 ) Actuarial loss (gain) 3,146 7,351 (139 ) (77 ) Special termination benefit 638 1,206 (8 ) — Net periodic benefit cost (credit) $ 9,160 $ 13,497 $ (473 ) $ (384 ) Six Months Ended June 30, Pension Postretirement Benefits 2016 2015 2016 2015 (Dollars in Thousands) Service cost $ 11,082 $ 11,505 $ 43 $ 68 Interest cost 17,938 16,575 432 464 Expected return on assets (18,848 ) (18,190 ) — — Amortization of: Prior service cost (credit) 175 211 (981 ) (1,150 ) Actuarial loss (gain) 6,036 10,700 (249 ) (154 ) Settlement charge 59 — — — Special termination benefit 764 1,462 (8 ) — Net periodic benefit cost (credit) $ 17,206 $ 22,263 $ (763 ) $ (772 )

Business Segments (Tables)

Business Segments (Tables)	6 Months Ended
	Jun. 30, 2016
Segment Reporting [Abstract]
Financial Data for Continuing Operation For Corporation's Reportable Business Segments	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, exclude intersegment sales, which are eliminated. Three Months Ended Six Months Ended June 30, June 30, 2016 2015 2016 2015 (Dollars in Thousands) Total revenues Mid-America Group $ 278,676 $ 257,649 $ 465,023 $ 398,482 Southeast Group 87,600 81,518 159,271 146,195 West Group 484,918 411,235 877,913 731,807 Total Aggregates Business 851,194 750,402 1,502,207 1,276,484 Cement 62,468 105,899 136,019 207,999 Magnesia Specialties 63,636 65,118 127,806 128,282 Total $ 977,298 $ 921,419 $ 1,766,032 $ 1,612,765 Net sales Mid-America Group $ 258,988 $ 237,415 $ 432,360 $ 367,120 Southeast Group 82,676 76,483 149,961 136,253 West Group 455,115 375,489 819,040 662,570 Total Aggregates Business 796,779 689,387 1,401,361 1,165,943 Cement 59,791 100,405 129,664 196,970 Magnesia Specialties 58,866 60,457 118,371 119,211 Total $ 915,436 $ 850,249 $ 1,649,396 $ 1,482,124 Earnings (Loss) from operations Mid-America Group $ 80,552 $ 66,894 $ 94,976 $ 62,691 Southeast Group 11,548 4,818 18,519 3,269 West Group 77,404 49,177 116,201 63,676 Total Aggregates Business 169,504 120,889 229,696 129,636 Cement 21,309 22,468 47,626 34,697 Magnesia Specialties 19,227 18,751 39,791 36,541 Corporate (22,298 ) (25,124 ) (45,601 ) (38,319 ) Total $ 187,742 $ 136,984 $ 271,512 $ 162,555
Net Sales By Product Line	The Aggregates business includes the aggregates product line and aggregates-related downstream product lines, which include asphalt, ready mixed concrete and road paving products. 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, 2016 2015 2016 2015 (Dollars in Thousands) Net sales Aggregates $ 516,283 $ 481,616 $ 922,721 $ 813,830 Asphalt and Paving 65,609 58,021 76,967 74,790 Ready Mixed Concrete 214,887 149,750 401,673 277,323 Total Aggregates Business 796,779 689,387 1,401,361 1,165,943 Cement 59,791 100,405 129,664 196,970 Magnesia Specialties 58,866 60,457 118,371 119,211 Total $ 915,436 $ 850,249 $ 1,649,396 $ 1,482,124 Gross profit (loss) Aggregates $ 164,353 $ 137,272 $ 245,431 $ 178,690 Asphalt and Paving 12,876 7,891 6,714 3,116 Ready Mixed Concrete 25,293 9,341 43,380 11,424 Total Aggregates Business 202,522 154,504 295,525 193,230 Cement 24,002 30,414 56,559 49,400 Magnesia Specialties 21,692 21,224 44,662 41,402 Corporate (1,515 ) (5,989 ) (5,411 ) (9,618 ) Total $ 246,701 $ 200,153 $ 391,335 $ 274,414

Supplemental Cash Flow Inform24

Supplemental Cash Flow Information (Tables)	6 Months Ended
	Jun. 30, 2016
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, 2016 2015 (Dollars in Thousands) Other current and noncurrent assets $ (9,691 ) $ (5,501 ) Accrued salaries, benefits and payroll taxes (7,808 ) (13,794 ) Accrued insurance and other taxes (256 ) (1,278 ) Accrued income taxes (8,495 ) (19,902 ) Accrued pension, postretirement and postemployment benefits 11,757 16,283 Other current and noncurrent liabilities (8,002 ) (4,878 ) $ (22,495 ) $ (29,070 )
Schedule Of Noncash Investing and Financing Activities	Noncash investing and financing activities are as follows: Six Months Ended June 30, 2016 2015 (Dollars in Thousands) Noncash investing and financing activities: Acquisition of assets through capital lease $ — $ 1,331 Acquisition of assets through asset exchange — 5,000

Significant Accounting Polici25

Significant Accounting Policies - Additional Information (Detail)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2016USD ($)State	Jun. 30, 2015USD ($)	Jun. 30, 2016USD ($)FacilityStateSegment	Jun. 30, 2015USD ($)	Dec. 31, 2015USD ($)
Significant Accounting Policies [Line Items]
Number of quarries distribution facilities and plants | Facility			400
Number of states with aggregates business sales by destination | State	26		26
Number of reportable segments | Segment			3
Other comprehensive loss before reclassifications for pension and postretirement benefit plans, tax benefit	$ 2,346,000	$ 6,793,000	$ 2,405,000	$ 6,904,000
Restatement Adjustment | Other Noncurrent Assets
Significant Accounting Policies [Line Items]
Debt issuance cost		4,130,000		4,130,000	$ 3,588,000
Restatement Adjustment | Other Current Assets
Significant Accounting Policies [Line Items]
Debt issuance cost		$ 533,000		$ 533,000	$ 533,000
Product Concentration Risk | Sales Revenue Segment | Cement
Significant Accounting Policies [Line Items]
Total net sales, percentage			8.00%		11.00%
Product Concentration Risk | Sales Revenue Segment | Magnesia Specialties
Significant Accounting Policies [Line Items]
Total net sales, percentage			7.00%		7.00%
Aggregates Product Line | Product Concentration Risk | Product Line Sales
Significant Accounting Policies [Line Items]
Total net sales, percentage			56.00%		55.00%
Aggregates-Related Downstream Product Lines | Product Concentration Risk | Product Line Sales
Significant Accounting Policies [Line Items]
Total net sales, percentage			29.00%		27.00%

Comprehensive Earnings Attribut

Comprehensive Earnings Attributable to Martin Marietta Materials Incorporated (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Statement Of Income And Comprehensive Income [Abstract]
Net earnings attributable to Martin Marietta Materials, Inc.	$ 122,052	$ 81,938	$ 167,047	$ 88,065
Other comprehensive loss, net of tax	(2,235)	(6,091)	(446)	(6,655)
Earnings attributable to Martin Marietta Materials, Inc.	$ 119,817	$ 75,847	$ 166,601	$ 81,410

Comprehensive Earnings Attrib27

Comprehensive Earnings Attributable to Noncontrolling Interests (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Statement Of Income And Comprehensive Income [Abstract]
Net earnings attributable to noncontrolling interests	$ 61	$ 41	$ 122	$ 73
Other comprehensive earnings, net of tax	2	2	33	5
Comprehensive earnings attributable to noncontrolling interests	$ 63	$ 43	$ 155	$ 78

Changes in Accumulated Other Co

Changes in Accumulated Other Comprehensive (Loss) Earnings, Net of Tax (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	$ (103,833)	$ (106,723)	$ (105,622)	$ (106,159)
Other comprehensive (loss) earnings before reclassifications, net of tax	(3,968)	(10,441)	(3,947)	(12,904)
Amounts reclassified from accumulated other comprehensive earnings, net of tax	1,733	4,350	3,501	6,249
Other comprehensive (loss) earnings, net of tax	(2,235)	(6,091)	(446)	(6,655)
Balance at end of period	(106,068)	(112,814)	(106,068)	(112,814)
Pension and Postretirement Benefit Plans
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(101,907)	(105,151)	(103,380)	(106,688)
Other comprehensive (loss) earnings before reclassifications, net of tax	(3,736)	(10,670)	(3,830)	(10,845)
Amounts reclassified from accumulated other comprehensive earnings, net of tax	1,529	4,158	3,096	5,870
Other comprehensive (loss) earnings, net of tax	(2,207)	(6,512)	(734)	(4,975)
Balance at end of period	(104,114)	(111,663)	(104,114)	(111,663)
Foreign Currency
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(149)	990	(264)	3,278
Other comprehensive (loss) earnings before reclassifications, net of tax	(232)	229	(117)	(2,059)
Other comprehensive (loss) earnings, net of tax	(232)	229	(117)	(2,059)
Balance at end of period	(381)	1,219	(381)	1,219
Unamortized Value of Terminated Forward Starting Interest Rate Swap
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(1,777)	(2,562)	(1,978)	(2,749)
Amounts reclassified from accumulated other comprehensive earnings, net of tax	204	192	405	379
Other comprehensive (loss) earnings, net of tax	204	192	405	379
Balance at end of period	$ (1,573)	$ (2,370)	$ (1,573)	$ (2,370)

Noncurrent Deferred Tax Assets

Noncurrent Deferred Tax Assets Recorded in Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Equity [Abstract]
Balance at beginning of period, Pension and Postretirement Benefit Plans	$ 65,523	$ 67,552	$ 66,467	$ 68,568
Other comprehensive earnings, tax effect, Pension and Postretirement Benefit Plans	1,408	4,073	464	3,057
Balance at end of period, Pension and Postretirement Benefit Plans	66,931	71,625	66,931	71,625
Balance at beginning of period, Unamortized Value of Terminated Forward Starting Interest Rate Swap	1,159	1,679	1,290	1,799
Other comprehensive earnings, tax effect, Unamortized Value of Terminated Forward Starting Interest Rate Swap	(136)	(125)	(267)	(245)
Balance at end of period, Unamortized Value of Terminated Forward Starting Interest Rate Swap	1,023	1,554	1,023	1,554
Balance at beginning of period, Net Non current Deferred Tax Assets	66,682	69,231	67,757	70,367
Other comprehensive earnings, tax effect, Net Non current Deferred Tax Assets	1,272	3,948	197	2,812
Balance at end of period, Net Non current Deferred Tax Assets	$ 67,954	$ 73,179	$ 67,954	$ 73,179

Reclassifications Out of Accumu

Reclassifications Out of Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest expense	$ 20,294	$ 19,087	$ 40,328	$ 38,418
Earnings from Continuing Operations	1,733	4,350	3,501	6,249
Pension and Postretirement Benefit Plans
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Earnings from Continuing Operations	1,529	4,158	3,096	5,870
Unamortized Value of Terminated Forward Starting Interest Rate Swap
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Earnings from Continuing Operations	204	192	405	379
Reclassification out of Accumulated Other Comprehensive Income | Pension and Postretirement Benefit Plans
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Settlement charge			59
Prior service credit	(518)	(469)	(806)	(939)
Actuarial loss	3,007	7,274	5,787	10,546
Income tax benefit	(960)	(2,647)	(1,944)	(3,737)
Earnings from Continuing Operations	1,529	4,158	3,096	5,870
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	2,489	6,805	5,040	9,607
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	340	317	672	624
Income tax benefit	(136)	(125)	(267)	(245)
Earnings from Continuing Operations	$ 204	$ 192	$ 405	$ 379

Basic and Diluted Earnings Per

Basic and Diluted Earnings Per Common Share (Detail) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Earnings Per Share [Abstract]
Net earnings from continuing operations attributable to Martin Marietta Materials, Inc.	$ 122,052	$ 81,938	$ 167,047	$ 88,065
Less: Distributed and undistributed earnings attributable to unvested awards	519	(876)	730	403
Basic and diluted net earnings available to common shareholders attributable to Martin Marietta Materials, Inc.	$ 121,533	$ 82,814	$ 166,317	$ 87,662
Basic weighted-average common shares outstanding	63,532	67,373	63,845	67,392
Effect of dilutive employee and director awards	270	260	246	262
Diluted weighted-average common shares outstanding	63,802	67,633	64,091	67,654

Inventories Net (Detail)

Inventories Net (Detail) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015	Jun. 30, 2015
Inventory Disclosure [Abstract]
Finished products	$ 463,807	$ 433,649	$ 425,732
Products in process and raw materials	60,324	55,194	62,059
Supplies and expendable parts	113,110	110,882	112,592
Inventories, Gross	637,241	599,725	600,383
Less: Allowances	(132,364)	(130,584)	(120,527)
Total	$ 504,877	$ 469,141	$ 479,856

Long-Term Debt (Detail)

Long-Term Debt (Detail) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015	Jun. 30, 2015
Debt Instrument [Line Items]
Total debt	$ 1,779,217	$ 1,568,774	$ 1,653,338
Less: Current maturities	(238,155)	(18,713)	(15,433)
Long-term debt	1,541,062	1,550,061	1,637,905
6.6% Senior Notes, Due 2018
Debt Instrument [Line Items]
Total debt	299,294	299,113	298,931
7% Debentures, Due 2025
Debt Instrument [Line Items]
Total debt	124,046	124,002	123,960
6.25% Senior Notes, Due 2037
Debt Instrument [Line Items]
Total debt	227,947	227,917	227,898
4.25% Senior Notes, Due 2024
Debt Instrument [Line Items]
Total debt	394,977	394,690	394,441
Floating Rate Notes, Due 2017
Debt Instrument [Line Items]
Total debt	298,793	298,868	298,514
Term Loan Facility, Due 2018
Debt Instrument [Line Items]
Total debt	213,571	222,521	228,346
Trade Receivable Facility
Debt Instrument [Line Items]
Total debt	220,000		80,000
Other Notes
Debt Instrument [Line Items]
Total debt	$ 589	$ 1,663	$ 1,248

Long-Term Debt (Parenthetical)

Long-Term Debt (Parenthetical) (Detail)	6 Months Ended
	Jun. 30, 2016	Dec. 31, 2015	Jun. 30, 2015
6.6% Senior Notes, Due 2018
Debt Instrument [Line Items]
Maturity year	2,018
Interest rate on notes	6.60%
7% Debentures, Due 2025
Debt Instrument [Line Items]
Maturity year	2,025
Interest rate on notes	7.00%
6.25% Senior Notes, Due 2037
Debt Instrument [Line Items]
Maturity year	2,037
Interest rate on notes	6.25%
4.25% Senior Notes, Due 2024
Debt Instrument [Line Items]
Maturity year	2,024
Interest rate on notes	4.25%
Floating Rate Notes, Due 2017
Debt Instrument [Line Items]
Maturity year	2,017
Interest rate	1.73%	1.71%	1.38%
Term Loan Facility, Due 2018
Debt Instrument [Line Items]
Maturity year	2,018
Interest rate	1.96%	1.86%	1.69%
Trade Receivable Facility
Debt Instrument [Line Items]
Credit Facility interest rate	1.16%		0.88%

Long-Term Debt - Additional inf

Long-Term Debt - Additional information (Detail) - USD ($)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2014	Dec. 31, 2015
Debt Instrument [Line Items]
Maximum consolidated debt reduction for unrestricted cash and cash equivalents for debt covenant calculation			$ 200,000,000
Additional interest expense	$ 340,000	$ 317,000	672,000	$ 624,000
Maximum | Texas Industries Inc.
Debt Instrument [Line Items]
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
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
Trade Receivable Facility
Debt Instrument [Line Items]
Credit facility commitment	250,000,000		$ 250,000,000
Debt instrument maturity period			Sep. 30, 2016
Credit facility borrowing base	391,600,000	$ 450,791,000	$ 391,600,000	$ 450,791,000		$ 282,258,000
Trade Receivable Facility | London Interbank Offered Rate(LIBOR)
Debt Instrument [Line Items]
Basis spread on variable rate			0.70%
Term Loan Facility
Debt Instrument [Line Items]
Credit facility commitment	$ 250,000,000		$ 250,000,000
Floating Rate Notes, Due 2017
Debt Instrument [Line Items]
Maturity date			Jun. 30, 2017
Maturity year			2,017
6.6% Senior Notes, Due 2018
Debt Instrument [Line Items]
Interest rate on notes	6.60%		6.60%
Maturity year			2,018
Increase in annual interest expense due to ongoing amortization of the terminated value of the swap agreements			$ 1,400,000

Financial Instruments - Additio

Financial Instruments - Additional Information (Detail) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015	Jun. 30, 2015
Fair Value Disclosures [Abstract]
Long-term debt, carrying values	$ 1,779,217	$ 1,568,774	$ 1,653,338
Long-term debt, fair values	$ 1,890,319	$ 1,625,193	$ 1,729,511

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail)	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Income Tax Disclosure [Abstract]
Effective income tax rate	30.40%	30.20%

Schedule of Components of Net P

Schedule of Components of Net Periodic Benefit Cost (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Pension
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 5,776	$ 5,513	$ 11,082	$ 11,505
Interest cost	9,331	8,213	17,938	16,575
Expected return on assets	(9,822)	(8,887)	(18,848)	(18,190)
Prior service cost (credit)	91	101	175	211
Actuarial loss (gain)	3,146	7,351	6,036	10,700
Settlement charge			59
Special termination benefit	638	1,206	764	1,462
Net periodic benefit cost (credit)	9,160	13,497	17,206	22,263
Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	24	34	43	68
Interest cost	259	229	432	464
Prior service cost (credit)	(609)	(570)	(981)	(1,150)
Actuarial loss (gain)	(139)	(77)	(249)	(154)
Special termination benefit	(8)		(8)
Net periodic benefit cost (credit)	$ (473)	$ (384)	$ (763)	$ (772)

Pension and Postretirement Be39

Pension and Postretirement Benefits - Additional Information (Detail)	6 Months Ended
	Jun. 30, 2016USD ($)
SERP Plans
Defined Benefit Plan Disclosure [Line Items]
Estimated contribution of pension plans	$ 38,752,000

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail) - USD ($)	6 Months Ended
	Jun. 30, 2016	Dec. 31, 2015	Jun. 30, 2015
Commitments and Contingencies [Line Items]
Guarantee of affiliate's obligations	$ 25,000,000
Due from affiliate	$ 6,000,000	$ 6,000,000	$ 6,000,000
Percentage of employees represented in labor union	10.00%
Woodville
Commitments and Contingencies [Line Items]
Collective bargaining agreement expiration month year	2018-05
Magnesia Specialties
Commitments and Contingencies [Line Items]
Percentage of employees represented in labor union	100.00%
Collective bargaining agreement expiration month year	2019-08

Business Segments - Additional

Business Segments - Additional Information (Detail)	3 Months Ended		6 Months Ended
	Jun. 30, 2016USD ($)	Jun. 30, 2015USD ($)	Jun. 30, 2016USD ($)Segment	Jun. 30, 2015USD ($)
Segment Reporting Information [Line Items]
Reportable business segments | Segment			3
Total revenues	$ 977,298,000	$ 921,419,000	$ 1,766,032,000	$ 1,612,765,000
Net Sales	915,436,000	850,249,000	1,649,396,000	1,482,124,000
Earnings (Loss) from Operations	187,742,000	136,984,000	271,512,000	162,555,000
Gross profit (loss)	246,701,000	200,153,000	391,335,000	274,414,000
Operating Segments | Cement
Segment Reporting Information [Line Items]
Total revenues	62,468,000	105,899,000	136,019,000	207,999,000
Net Sales	59,791,000	100,405,000	129,664,000	196,970,000
Earnings (Loss) from Operations	21,309,000	22,468,000	47,626,000	34,697,000
Operating Segments | Cement | California
Segment Reporting Information [Line Items]
Total revenues		35,318,000		69,674,000
Net Sales		34,160,000		67,267,000
Earnings (Loss) from Operations		485,000		7,906,000
Gross profit (loss)		3,424,000		(647,000)
Intersegment Eliminations | Cement
Segment Reporting Information [Line Items]
Total revenues	$ 27,649,000	$ 20,854,000	$ 54,637,000	$ 38,955,000

Financial Data for Continuing O

Financial Data for Continuing Operations for Corporations Reportable Business Segments (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Segment Reporting Information [Line Items]
Total revenues	$ 977,298	$ 921,419	$ 1,766,032	$ 1,612,765
Net Sales	915,436	850,249	1,649,396	1,482,124
Earnings (Loss) from Operations	187,742	136,984	271,512	162,555
Aggregates Business
Segment Reporting Information [Line Items]
Total revenues	851,194	750,402	1,502,207	1,276,484
Net Sales	796,779	689,387	1,401,361	1,165,943
Earnings (Loss) from Operations	169,504	120,889	229,696	129,636
Operating Segments | Mid-America Group | Aggregates Business
Segment Reporting Information [Line Items]
Total revenues	278,676	257,649	465,023	398,482
Net Sales	258,988	237,415	432,360	367,120
Earnings (Loss) from Operations	80,552	66,894	94,976	62,691
Operating Segments | Southeast Group | Aggregates Business
Segment Reporting Information [Line Items]
Total revenues	87,600	81,518	159,271	146,195
Net Sales	82,676	76,483	149,961	136,253
Earnings (Loss) from Operations	11,548	4,818	18,519	3,269
Operating Segments | West Group | Aggregates Business
Segment Reporting Information [Line Items]
Total revenues	484,918	411,235	877,913	731,807
Net Sales	455,115	375,489	819,040	662,570
Earnings (Loss) from Operations	77,404	49,177	116,201	63,676
Operating Segments | Cement
Segment Reporting Information [Line Items]
Total revenues	62,468	105,899	136,019	207,999
Net Sales	59,791	100,405	129,664	196,970
Earnings (Loss) from Operations	21,309	22,468	47,626	34,697
Operating Segments | Magnesia Specialties
Segment Reporting Information [Line Items]
Total revenues	63,636	65,118	127,806	128,282
Net Sales	58,866	60,457	118,371	119,211
Earnings (Loss) from Operations	19,227	18,751	39,791	36,541
Corporate
Segment Reporting Information [Line Items]
Earnings (Loss) from Operations	$ (22,298)	$ (25,124)	$ (45,601)	$ (38,319)

Net Sales and Gross Profit by L

Net Sales and Gross Profit by Line of Business (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Product Information [Line Items]
Net Sales	$ 915,436	$ 850,249	$ 1,649,396	$ 1,482,124
Gross profit (loss), Total	246,701	200,153	391,335	274,414
Corporate
Product Information [Line Items]
Gross profit (loss), Total	(1,515)	(5,989)	(5,411)	(9,618)
Aggregates
Product Information [Line Items]
Net Sales	516,283	481,616	922,721	813,830
Gross profit (loss), Total	164,353	137,272	245,431	178,690
Asphalt and Paving
Product Information [Line Items]
Net Sales	65,609	58,021	76,967	74,790
Gross profit (loss), Total	12,876	7,891	6,714	3,116
Ready Mixed Concrete
Product Information [Line Items]
Net Sales	214,887	149,750	401,673	277,323
Gross profit (loss), Total	25,293	9,341	43,380	11,424
Aggregates Business
Product Information [Line Items]
Net Sales	796,779	689,387	1,401,361	1,165,943
Gross profit (loss), Total	202,522	154,504	295,525	193,230
Cement
Product Information [Line Items]
Net Sales	59,791	100,405	129,664	196,970
Gross profit (loss), Total	24,002	30,414	56,559	49,400
Magnesia Specialties
Product Information [Line Items]
Net Sales	58,866	60,457	118,371	119,211
Gross profit (loss), Total	$ 21,692	$ 21,224	$ 44,662	$ 41,402

Components of Change in Other A

Components of Change in Other Assets and Liabilities Net (Detail) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Supplemental Cash Flow Elements [Abstract]
Other current and noncurrent assets	$ (9,691)	$ (5,501)
Accrued salaries, benefits and payroll taxes	(7,808)	(13,794)
Accrued insurance and other taxes	(256)	(1,278)
Accrued income taxes	(8,495)	(19,902)
Accrued pension, postretirement and postemployment benefits	11,757	16,283
Other current and noncurrent liabilities	(8,002)	(4,878)
Change in other assets and liabilities	$ (22,495)	$ (29,070)

Noncash Investing and Financing

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

Business Combination - Addition

Business Combination - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2016T
Colorado | Minimum
Business Combinations [Line Items]
Acquisition of mineral reserves	500,000,000

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended
	Mar. 31, 2016	Jun. 30, 2016	Jun. 30, 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense		$ 12,801	$ 7,524
Performance Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of awards, granted	75,421
Weighted average grant-date fair value of stock awards, granted	$ 142.02
Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of awards, granted	68,720
Weighted average grant-date fair value of stock awards, granted	$ 124.41
Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock options expected to be awarded		0