Significant Accounting Policies (Tables)

3 Months Ended

Mar. 31, 2019

Significant Accounting Policies [Line Items]

Changes in Accumulated Other Comprehensive Earnings Net of Tax

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

	(Dollars in Thousands)
	Pension and Postretirement Benefit Plans			Foreign Currency			Unamortized Value of Terminated Forward Starting Interest Rate Swap			Accumulated Other Comprehensive Loss
	Three Months Ended March 31, 2019
Balance at beginning of period	$	(141,505	)	$	(2,074	)	$	—		$	(143,579	)
Other comprehensive earnings before    reclassifications, net of tax		—			497			—			497
Amounts reclassified from accumulated    other comprehensive loss, net of tax		2,758			—			—			2,758
Other comprehensive earnings, net of tax		2,758			497			—			3,255
Balance at end of period	$	(138,747	)	$	(1,577	)	$	—		$	(140,324	)
	Three Months Ended March 31, 2018
Balance at beginning of period	$	(128,802	)	$	(22	)	$	(280	)	$	(129,104	)
Other comprehensive loss before    reclassifications, net of tax		—			(587	)		—			(587	)
Amounts reclassified from accumulated    other comprehensive loss, net of tax		1,996			—			210			2,206
Other comprehensive earnings (loss), net of tax		1,996			(587	)		210			1,619
Balance at end of period	$	(126,806	)	$	(609	)	$	(70	)	$	(127,485	)

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)
	Pension and Postretirement Benefit Plans			Unamortized Value of Terminated Forward Starting Interest Rate Swap			Net Noncurrent Deferred Tax Assets
	Three Months Ended March 31, 2019
Balance at beginning of period	$	84,207		$	—		$	84,207
Tax effect of other comprehensive earnings		(868	)		—			(868	)
Balance at end of period	$	83,339		$	—		$	83,339
	Three Months Ended March 31, 2018
Balance at beginning of period	$	79,938		$	178		$	80,116
Tax effect of other comprehensive earnings		(658	)		(137	)		(795	)
Balance at end of period	$	79,280		$	41		$	79,321

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 consolidated
	March 31,						statements of earnings and
	2019			2018			comprehensive earnings
	(Dollars in Thousands)
Pension and postretirement benefit plans
Amortization of:
Prior service credit	$	(188	)	$	(585	)
Actuarial loss		3,814			3,239
		3,626			2,654		Other nonoperating income, net
Tax benefit		(868	)		(658	)	Income tax (benefit) expense
	$	2,758		$	1,996
Unamortized value of terminated    forward starting interest rate swap
Additional interest expense	$	—		$	347		Interest expense
Tax benefit		—			(137	)	Income tax (benefit) expense
	$	—		$	210

Basic and Diluted Earnings Per Common Share

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

	Three Months Ended
	March 31,
	2019		2018
	(In Thousands)
Net earnings attributable to Martin Marietta    Materials, Inc.	$	42,853	$	10,023
Less: Distributed and undistributed earnings    attributable to unvested awards		86		63
Basic and diluted net earnings available to common    shareholders attributable to Martin Marietta    Materials, Inc.	$	42,767	$	9,960
Basic weighted-average common shares outstanding		62,584		62,957
Effect of dilutive employee and director awards		193		265
Diluted weighted-average common shares outstanding		62,777		63,222

Parent

Significant Accounting Policies [Line Items]

Comprehensive Earnings

Comprehensive earnings attributable to Martin Marietta is as follows:

	Three Months Ended
	March 31,
	2019		2018
	(Dollars in Thousands)
Net earnings attributable to Martin Marietta Materials, Inc.	$	42,853	$	10,023
Other comprehensive earnings, net of tax		3,255		1,619
Comprehensive earnings attributable to Martin Marietta    Materials, Inc.	$	46,108	$	11,642

Noncontrolling Interests

Significant Accounting Policies [Line Items]

Comprehensive Earnings

Comprehensive earnings attributable to noncontrolling interests consist of net earnings and adjustments for the funded status of pension and postretirement benefit plans.  For the three months ended March 31, 2019 and 2018, there were no other comprehensive earnings attributable to noncontrolling interests.