Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 31,085	$ 28,965	$ 22,669
Other comprehensive income, net of tax:
Unrecognized actuarial gain (loss), net of tax	216	(665)	(98)
Foreign currency translation adjustments, net of tax	1,288	182	(850)
Comprehensive income	$ 32,589	$ 28,482	$ 21,721