Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Statement of Comprehensive Income [Abstract]
Net earnings	$ 84,623	$ 79,671	$ 78,573
Other comprehensive income/(loss), net of tax:
Net foreign currency translation adjustment	12,829	(891)	(2,982)
Unrealized loss on cash flow hedge, net of taxes of $809 and $372 at December 31, 2020 and 2019, respectively	(2,285)	(1,399)	0
Net change in postretirement benefit plan, net of taxes of $127, $101, and $434 at December 31, 2020, 2019 and 2018, respectively	(807)	328	1,022
Other comprehensive income/(loss), net of tax	9,737	(1,962)	(1,960)
Comprehensive income	$ 94,360	$ 77,709	$ 76,613