Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 137,890	$ 107,583	$ 358,935	$ 204,358
Other comprehensive loss:
Foreign currency translation adjustments	(14,095)	(7,771)	(10,744)	(26,046)
Change in unrealized gain (loss) on investments, net of income tax (provision) benefit of $(52), $(494), $(1,153) and $78 for the three and nine months ended September 30, 2019 and 2018, respectively	155	1,524	3,232	(242)
Other comprehensive loss	(13,940)	(6,247)	(7,512)	(26,288)
Comprehensive income	$ 123,950	$ 101,336	$ 351,423	$ 178,070

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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