Significant Accounting Policies (Tables)

6 Months Ended

Jun. 30, 2018

Significant Accounting Policies [Line Items]

Changes in Accumulated Other Comprehensive Earnings (Loss), Net of Tax

Changes in accumulated other comprehensive earnings (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 June 30, 2018
Balance at beginning of period	$	(126,806	)	$	(609	)	$	(70	)	$	(127,485	)
Other comprehensive loss before    reclassifications, net of tax		—			(476	)		—			(476	)
Amounts reclassified from accumulated    other comprehensive earnings, net of tax		2,008			—			70			2,078
Other comprehensive earnings (loss), net of tax		2,008			(476	)		70			1,602
Balance at end of period	$	(124,798	)	$	(1,085	)	$	—		$	(125,883	)
	Three-Months Ended June 30, 2017
Balance at beginning of period	$	(126,463	)	$	(1,025	)	$	(937	)	$	(128,425	)
Other comprehensive earnings before    reclassifications, net of tax		—			389			—			389
Amounts reclassified from accumulated    other comprehensive earnings, net of tax		1,910			—			220			2,130
Other comprehensive earnings, net of tax		1,910			389			220			2,519
Balance at end of period	$	(124,553	)	$	(636	)	$	(717	)	$	(125,906	)

1. Significant Accounting Policies (continued)

Consolidated Comprehensive Earnings/Loss and Accumulated Other Comprehensive Loss (continued)

	(Dollars in Thousands)
							Unamortized
							Value of
							Terminated			Accumulated
	Pension and						Forward Starting			Other
	Postretirement			Foreign			Interest Rate			Comprehensive
	Benefit Plans			Currency			Swap			Loss
	Six-Months Ended June 30, 2018
Balance at beginning of period	$	(128,802	)	$	(22	)	$	(280	)	$	(129,104	)
Other comprehensive loss before    reclassifications, net of tax		—			(1,063	)		—			(1,063	)
Amounts reclassified from accumulated    other comprehensive earnings, net of tax		4,004			—			280			4,284
Other comprehensive earnings (loss), net of tax		4,004			(1,063	)		280			3,221
Balance at end of period	$	(124,798	)	$	(1,085	)	$	—		$	(125,883	)
	Six-Months Ended June 30, 2017
Balance at beginning of period	$	(128,373	)	$	(1,162	)	$	(1,152	)	$	(130,687	)
Other comprehensive earnings before    reclassifications, net of tax		—			526			—			526
Amounts reclassified from accumulated    other comprehensive earnings, net of tax		3,820			—			435			4,255
Other comprehensive earnings, net of tax		3,820			526			435			4,781
Balance at end of period	$	(124,553	)	$	(636	)	$	(717	)	$	(125,906	)

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 June 30, 2018
Balance at beginning of period	$	79,280		$	41		$	79,321
Tax effect of other comprehensive earnings		(661	)		(41	)		(702	)
Balance at end of period	$	78,619		$	-		$	78,619
	Three-Months Ended June 30, 2017
Balance at beginning of period	$	80,859		$	608		$	81,467
Tax effect of other comprehensive earnings		(1,184	)		(144	)		(1,328	)
Balance at end of period	$	79,675		$	464		$	80,139
	Six-Months Ended June 30, 2018
Balance at beginning of period	$	79,938		$	178		$	80,116
Tax effect of other comprehensive earnings		(1,319	)		(178	)		(1,497	)
Balance at end of period	$	78,619		$	-		$	78,619
	Six-Months Ended June 30, 2017
Balance at beginning of period	$	82,044		$	749		$	82,793
Tax effect of other comprehensive earnings		(2,369	)		(285	)		(2,654	)
Balance at end of period	$	79,675		$	464		$	80,139

Reclassification Out of Accumulated Other Comprehensive Loss

1. Significant Accounting Policies (continued)

Consolidated Comprehensive Earnings/Loss and Accumulated Other Comprehensive Loss (continued)

Reclassifications out of accumulated other comprehensive loss are as follows:

	Three-Months Ended						Six-Months Ended						Affected line items in the consolidated
	June 30,						June 30,						statements of earnings and
	2018			2017			2018			2017			comprehensive earnings
	(Dollars in Thousands)
Pension and postretirement benefit plans
Amortization of:
Prior service credit	$	(400	)	$	(358	)		(985	)		(716	)
Actuarial loss		3,069			3,452			6,308			6,905
		2,669			3,094			5,323			6,189		Other nonoperating income, net
Tax benefit		(661	)		(1,184	)		(1,319	)		(2,369	)	Income tax expense
	$	2,008		$	1,910		$	4,004		$	3,820
Unamortized value of terminated    forward starting interest rate swap
Additional interest expense	$	111		$	364		$	458		$	720		Interest expense
Tax benefit		(41	)		(144	)		(178	)		(285	)	Income tax expense
	$	70		$	220		$	280		$	435

Basic and Diluted Earnings Per Common Share

1. Significant Accounting Policies (continued)

Earnings per Common Share

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

	Three-Months Ended				Six-Months Ended
	June 30,				June 30,
	2018		2017		2018		2017
	(In Thousands)
Net earnings attributable to Martin Marietta Materials, Inc.	$	185,377	$	142,279	$	195,400	$	184,613
Less: Distributed and undistributed earnings    attributable to unvested awards		317		413		378		553
Basic and diluted net earnings available to common    shareholders attributable to Martin Marietta Materials, Inc.	$	185,060	$	141,866	$	195,022	$	184,060
Basic weighted-average common shares outstanding		63,021		62,858		62,989		62,961
Effect of dilutive employee and director awards		264		283		264		285
Diluted weighted-average common shares outstanding		63,285		63,141		63,253		63,246

Parent

Significant Accounting Policies [Line Items]

Comprehensive Earnings

Comprehensive earnings attributable to Martin Marietta is as follows:

	Three-Months Ended				Six-Months Ended
	June 30,				June 30,
	2018		2017		2018		2017
	(Dollars in Thousands)
Net earnings attributable to Martin Marietta Materials, Inc.	$	185,377	$	142,279	$	195,400	$	184,613
Other comprehensive earnings, net of tax		1,602		2,519		3,221		4,781
Comprehensive earnings attributable to Martin Marietta    Materials, Inc.	$	186,979	$	144,798	$	198,621	$	189,394

Noncontrolling Interests

Significant Accounting Policies [Line Items]

Comprehensive Earnings

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

	Three-Months Ended					Six-Months Ended
	June 30,					June 30,
	2018		2017			2018		2017
	(Dollars in Thousands)
Net earnings (loss) attributable to noncontrolling interests	$	126	$	(38	)	$	143	$	(65	)
Other comprehensive earnings, net of tax		—		1			1		2
Comprehensive earnings (loss) attributable to    noncontrolling interests	$	126	$	(37	)	$	144	$	(63	)