Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2016	Mar. 31, 2015
Statement of Comprehensive Income [Abstract]
Net earnings		$ 22,792	$ 34,976
Currency translation		721	(985)
Postretirement plans (1)	[1]	120	114
Comprehensive income		23,633	34,105
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net Unamortized Gain (Loss) Arising During Period, Tax		$ 75	$ 100

[1] Net of tax effect of $0.1 million for each of the three months ended March 31, 2016 and 2015.