Consolidated Statements of Earnings and Comprehensive Earnings (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Total Revenues	$ 1,420,246	$ 1,219,640	$ 3,638,668	$ 3,224,047
Total Cost of Revenues	999,601	906,656	2,718,250	2,484,754
Gross Profit	420,645	312,984	920,418	739,293
Selling, general & administrative expenses	78,281	68,441	228,955	209,632
Acquisition-related expenses, net		89	190	12,925
Other operating (income) and expense, net	(2,899)	3,792	(9,092)	(26,960)
Earnings from Operations	345,263	240,662	700,365	543,696
Interest expense	32,436	35,468	98,680	103,526
Other nonoperating (income) and expense, net	(1,973)	(4,248)	9,690	(19,873)
Earnings before income tax expense	314,800	209,442	591,995	460,043
Income tax expense	66,178	29,089	111,077	84,147
Consolidated net earnings	248,622	180,353	480,918	375,896
Less: Net earnings attributable to noncontrolling interests	49	132	17	275
Net Earnings Attributable to Martin Marietta Materials, Inc.	248,573	180,221	480,901	375,621
Consolidated Comprehensive Earnings:
Earnings attributable to Martin Marietta Materials, Inc.	251,142	184,613	489,715	383,234
Earnings attributable to noncontrolling interests	49	132	17	276
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	$ 251,191	$ 184,745	$ 489,732	$ 383,510
Net Earnings Attributable to Martin Marietta Materials, Inc. Per Common Share:
Basic attributable to common shareholders	$ 3.97	$ 2.86	$ 7.67	$ 5.95
Diluted attributable to common shareholders	$ 3.96	$ 2.85	$ 7.65	$ 5.93
Weighted-Average Common Shares Outstanding:
Basic	62,510	62,932	62,552	62,970
Diluted	62,679	63,167	62,725	63,224
Products and Services
Total Revenues	$ 1,323,160	$ 1,142,218	$ 3,397,599	$ 3,024,300
Total Cost of Revenues	901,844	828,110	2,474,333	2,282,159
Freight
Total Revenues	97,086	77,422	241,069	199,747
Total Cost of Revenues	$ 97,757	$ 78,546	$ 243,917	$ 202,595