Significant Accounting Policies (Tables)

3 Months Ended

Mar. 31, 2015

Significant Accounting Policies [Line Items]

Changes in Accumulated Other Comprehensive Earnings, Net of Tax

Changes in accumulated other comprehensive loss, net of tax, are as follows:

	(Dollars in Thousands)
							Unamortized
							Value of
							Terminated			Accumulated
	Pension and						Forward Starting			Other
	Postretirement			Foreign			Interest Rate			Comprehensive
	Benefit Plans			Currency			Swap			Loss
	Three Months Ended March 31, 2015
Balance at beginning of period	$	(106,688	)	$	3,278		$	(2,749	)	$	(106,159	)
Other comprehensive loss before reclassifications, net of tax		—			(2,288	)		—			(2,288	)
Amounts reclassified from accumulated other comprehensive loss, net of tax		1,537			—			187			1,724
Other comprehensive earnings (loss), net of tax		1,537			(2,288	)		187			(564	)
Balance at end of period	$	(105,151	)	$	990		$	(2,562	)	$	(106,723	)
	Three Months Ended March 31, 2014
Balance at beginning of period	$	(44,549	)	$	3,902		$	(3,467	)	$	(44,114	)
Other comprehensive earnings before reclassifications, net of tax		—			914			—			914
Amounts reclassified from accumulated other comprehensive loss, net of tax		282			—			174			456
Other comprehensive earnings, net of tax		282			914			174			1,370
Balance at end of period	$	(44,267	)	$	4,816		$	(3,293	)	$	(42,744	)

Noncurrent Deferred Tax Assets Recorded In Accumulated Other Comprehensive Loss

Changes in net noncurrent deferred tax assets recorded in accumulated other comprehensive loss are as follows:

	(Dollars in Thousands)
				Unamortized
				Value of			Net
	Pension and			Terminated			Noncurrent
	Postretirement			Forward Starting			Deferred Tax
	Benefit Plans			Interest Rate Swap			Assets
	Three Months Ended March 31, 2015
Balance at beginning of period	$	68,568		$	1,799		$	70,367
Tax effect of other comprehensive earnings		(1,016	)		(120	)		(1,136	)
Balance at end of period	$	67,552		$	1,679		$	69,231
	Three Months Ended March 31, 2014
Balance at beginning of period	$	29,198		$	2,269		$	31,467
Tax effect of other comprehensive earnings		(182	)		(114	)		(296	)
Balance at end of period	$	29,016		$	2,155		$	31,171

Reclassification Out of Accumulated Other Comprehensive Loss

Reclassifications out of accumulated other comprehensive loss are as follows:

	Three Months Ended						Affected line items in the
	March 31,						consolidated statements of earnings
	2015			2014			and comprehensive earnings
	(Dollars in Thousands)
Pension and postretirement benefit plans
Amortization of:
Prior service credit	$	(471	)	$	(703	)
Actuarial loss		3,026			1,167
		2,555			464		Cost of sales; Selling, general   and administrative expenses
Tax benefit		(1,016	)		(182	)	Income tax benefit
	$	1,539		$	282
Unamortized value of terminated forward starting interest    rate swap
Additional interest expense	$	307		$	288		Interest expense
Tax benefit		(120	)		(114	)	Income tax benefit
	$	187		$	174

Basic and Diluted Earnings (Loss) per Common Share

The following table reconciles the numerator and denominator for basic and diluted earnings (loss) per common share:

	Three Months Ended
	March 31,
	2015		2014
	(In Thousands)
Net earnings (loss) from continuing operations attributable to       Martin Marietta Materials, Inc.	$	6,126	$	(21,603	)
Less: Distributed and undistributed earnings attributable to unvested awards		1,369		67
Basic and diluted net earnings (loss) available to common shareholders from       continuing operations attributable to Martin Marietta Materials, Inc.		4,757		(21,670	)
Basic and diluted net loss available to common shareholders from       discontinued operations		—		(15	)
Basic and diluted net earnings (loss) available to common shareholders       attributable to Martin Marietta Materials, Inc.	$	4,757	$	(21,685	)
Basic weighted-average common shares outstanding		67,411		46,315
Effect of dilutive employee and director awards		265		—
Diluted weighted-average common shares outstanding		67,676		46,315

Parent

Significant Accounting Policies [Line Items]

Comprehensive Earnings (Loss)

Comprehensive earnings attributable to Martin Marietta is as follows:

	Three Months Ended
	March 31,
	2015			2014
	(Dollars in Thousands)
Net earnings (loss) attributable to Martin Marietta Materials, Inc.	$	6,126		$	(21,618	)
Other comprehensive (loss) earnings, net of tax		(564	)		1,370
Comprehensive earnings (loss) attributable to Martin Marietta Materials, Inc.	$	5,562		$	(20,248	)

Noncontrolling Interests

Significant Accounting Policies [Line Items]

Comprehensive Earnings (Loss)

Comprehensive earnings (loss) attributable to noncontrolling interests, consisting of net earnings or loss and adjustments for the funded status of pension and postretirement benefit plans, is as follows:

	Three Months Ended
	March 31,
	2015		2014
	(Dollars in Thousands)
Net earnings (loss) attributable to noncontrolling interests	$	33	$	(1,535	)
Other comprehensive earnings, net of tax		2		1
Comprehensive earnings (loss) attributable to noncontrolling interests	$	35	$	(1,534	)