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