Unaudited Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Statement of Comprehensive Income [Abstract]
Net income	$ 14,272	$ 8,968	$ 37,330	$ 25,173
Other comprehensive income (loss):
Foreign currency translation adjustment	(67)	(22)	(38)	(179)
Unrealized gain on investments available for sale	0	5	0	18
Comprehensive income	$ 14,205	$ 8,951	$ 37,292	$ 25,012