Condensed Consolidated Statements of Comprehensive Income (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Statement of Comprehensive Income [Abstract]
Net income	$ 5,374	$ 5,159
Other comprehensive income (loss):
Unrealized loss on marketable securities, net of income tax expense of $0 and $0	(13)	0
Foreign currency translation, net of income tax expense of $5 and $8	(164)	(147)
Comprehensive income	$ 5,197	$ 5,012