Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Statement of Comprehensive Income [Abstract]
Net income	$ 129,590	$ 51,517	$ 373,412	$ 119,930
Other comprehensive income (loss):
Foreign currency translation adjustments	5,678	2,357	22,604	5,453
Change in unrealized gains (losses) on available-for-sale securities, net of tax of $212, $(412), $378, and $810, respectively	328	(676)	599	1,325
Total other comprehensive income	6,006	1,681	23,203	6,778
Comprehensive income	$ 135,596	$ 53,198	$ 396,615	$ 126,708

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=51831270

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