Accumulated Other Comprehensive Income Roll Forward (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Jun. 30, 2017	Dec. 31, 2016
Accumulated Other Comprehensive Income (Loss) Roll Forward [Line Items]
Accumulated Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax	$ 0		$ 0		$ 0	$ 0
Unrealized gain on available-for-sale investments, net of tax (benefit)	0		0
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax	0	$ (2,249)	0	$ (2,359)
Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax	(31,033)		(31,033)		$ (38,736)	$ (54,649)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Gain (Loss) Arising During Period, Net of Tax	7,703		23,616
Foreign currency translation adjustment	7,703	(328)	23,616	(9,566)
Accumulated Other Comprehensive Income (Loss), Net of Tax, Beginning Balance	(38,736)		(54,649)
Other Comprehensive Income Loss Arising During Period Total Net of Tax	7,703		23,616
Other comprehensive income (loss), net of tax	7,703	$ (2,577)	23,616	$ (11,925)
Accumulated Other Comprehensive Income (Loss), Net of Tax, Ending Balance	$ (31,033)		$ (31,033)