Consolidated Statements of Earnings and Comprehensive Earnings (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Income Statement [Abstract]
Net Sales	$ 1,022,137	$ 1,038,344	$ 2,810,110	$ 2,687,740
Freight and delivery revenues	65,595	65,557	185,006	182,194
Total revenues	1,087,732	1,103,901	2,995,116	2,869,934
Cost of sales	730,459	745,037	2,097,272	2,001,752
Freight and delivery costs	65,595	65,557	185,006	182,194
Total cost of revenues	796,054	810,594	2,282,278	2,183,946
Gross Profit	291,678	293,307	712,838	685,988
Selling, general & administrative expenses	57,219	54,773	195,127	172,903
Acquisition-related expenses, net	1,314	306	3,319	853
Other operating expense (income), net	6,181	(4,441)	(2,575)	(7,309)
Earnings from Operations	226,964	242,669	516,967	519,541
Interest expense	23,141	20,568	68,037	60,896
Other nonoperating income, net	(479)	(8,246)	(6,434)	(12,016)
Earnings before taxes on income	204,302	230,347	455,364	470,661
Taxes on income	52,763	70,869	119,277	144,014
Consolidated net earnings	151,539	159,478	336,087	326,647
Less: Net (loss) earnings attributable to noncontrolling interests	(7)	(1)	(72)	121
Net Earnings Attributable to Martin Marietta Materials, Inc.	151,546	159,479	336,159	326,526
Consolidated Comprehensive Earnings: (See Note 1)
Earnings attributable to Martin Marietta Materials, Inc.	154,524	161,036	343,918	327,637
Earnings (Loss) attributable to noncontrolling interests	1	19	(62)	173
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	$ 154,525	$ 161,055	$ 343,856	$ 327,810
Net Earnings Attributable to Martin Marietta Materials, Inc. Per Common Share:
Basic attributable to common shareholders	$ 2.40	$ 2.50	$ 5.33	$ 5.10
Diluted attributable to common shareholders	$ 2.39	$ 2.49	$ 5.30	$ 5.08
Weighted-Average Common Shares Outstanding:
Basic	62,896	63,452	62,940	63,713
Diluted	63,158	63,723	63,218	63,967
Cash Dividends Per Common Share	$ 0.44	$ 0.42	$ 1.28	$ 1.22