Basic and Diluted Earnings Per Common Share (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Schedule of Earnings Per Share, Basic and Diluted, by Common Class
Net loss from continuing operations attributable to Martin Marietta Materials, Inc.	$ (21,603)	$ (27,551)
Less: Distributed and undistributed earnings attributable to unvested awards	67	93
Basic and diluted net loss available to common shareholders from continuing operations attributable to Martin Marietta Materials, Inc.	(21,670)	(27,644)
Basic and diluted net loss available to common shareholders from discontinued operations	(15)	(288)
Basic and diluted net loss available to common shareholders attributable to Martin Marietta Materials, Inc.	$ (21,685)	$ (27,932)
Basic and diluted weighted-average common shares outstanding	46,315	46,028