Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Statement of Comprehensive Income [Abstract]
Net earnings	$ 8,814	$ 6,281	$ 13,446	$ 9,188
Other comprehensive income (loss):
Foreign currency translation adjustment	(74)	153	66	(368)
Employee benefit funded status adjustment, net of tax	148	640	269	802
Comprehensive income	$ 8,888	$ 7,074	$ 13,781	$ 9,622