Accumulated Other Comprehensive Loss - Schedule of Accumulated Other Comprehensive Income (Loss) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2018 USD ($)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	$ 3,362,469
Other comprehensive (loss) income	(26,982)
Ending Balance	3,191,860
Accumulated Other Comprehensive Loss
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(21,930)
Ending Balance	(48,912)
Foreign Currency Translation
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(24,319)
Other comprehensive (loss) income	(27,585)
Ending Balance	(51,904)
Net Unrealized Gains (Losses) on Investments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	2,389
Other comprehensive (loss) income	603
Ending Balance	$ 2,992