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	$ 12,616	$ 5,385	$ 26,246	$ 25,833
Other comprehensive income, net of tax:
Unrealized gain (loss) on derivative instruments and other assets	958	627	(1,664)	1,627
Foreign currency translation adjustments	65,307	4,961	48,917	15,548
Equity in unrealized loss of an investee	0	(69)	0	(49)
Total comprehensive income	$ 78,881	$ 10,904	$ 73,499	$ 42,959