Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Statement of Comprehensive Income [Abstract]
Net income	$ 39,213	$ 51,324	$ 92,877	$ 93,942
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments	21,841	10,699	(10,693)	16,428
Total comprehensive income	$ 61,054	$ 62,023	$ 82,184	$ 110,370