Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Statement of Comprehensive Income [Abstract]
Net earnings	$ 8,327	$ 10,231	$ 20,455	$ 23,677
Other comprehensive income (loss):
Foreign currency translation adjustment	(170)	(1,203)	(330)	(1,137)
Pension and postretirement benefits, net of tax	123	567	362	836
Comprehensive income	$ 8,280	$ 9,595	$ 20,487	$ 23,376