Accumulated Other Comprehensive Income (Loss) - Schedule of Total Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	$ 473,974	$ 531,090	$ 184,945
Ending balance	383,454	473,974	531,090
Unrealized Gain (Loss) on Securities Available-for-Sale
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(417)	(868)	(174)
Current period other comprehensive income (loss)	35	451	(694)
Ending balance	(382)	(417)	(868)
Foreign Currency Translation Adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	1,322
Current period other comprehensive income (loss)	(10,110)	1,322
Reclassification from accumulated othercomprehensive income	3,490
Ending balance	(5,298)	1,322
Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	905	(868)	(174)
Current period other comprehensive income (loss)	(10,075)	1,773	(694)
Reclassification from accumulated othercomprehensive income	3,490
Ending balance	$ (5,680)	$ 905	$ (868)