Accumulated Other Comprehensive Loss - Schedule of Accumulated Other Comprehensive Income Loss (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balance as of January 1, 2017			$ 3,224,370
Other comprehensive gain	$ 13,393	$ (2,824)	23,702	$ 9,837
Balance as of June 30, 2017	3,287,172		3,287,172
Foreign Currency Translation
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balance as of January 1, 2017			(59,017)
Other comprehensive gain			22,572
Balance as of June 30, 2017	(36,445)		(36,445)
Net Unrealized Gains on Investments
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balance as of January 1, 2017			2,795
Other comprehensive gain			1,130
Balance as of June 30, 2017	3,925		3,925
Total
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balance as of January 1, 2017			(56,222)
Other comprehensive gain			23,702
Balance as of June 30, 2017	$ (32,520)		$ (32,520)