Unaudited 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 income	$ 11,041	$ 8,440	$ 23,058	$ 16,205
Other comprehensive income (loss):
Foreign currency translation adjustment	178	(137)	29	(157)
Unrealized gain on investments available for sale	0	13	0	13
Comprehensive income	$ 11,219	$ 8,316	$ 23,087	$ 16,061