Comprehensive Earnings Attributable to Martin Marietta Materials Incorporated (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Statement Of Income And Comprehensive Income [Abstract]
Net earnings attributable to Martin Marietta Materials, Inc.	$ 10,023	$ 42,334
Other comprehensive earnings, net of tax	1,619	2,262
Earnings attributable to Martin Marietta Materials, Inc.	$ 11,642	$ 44,596

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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