Consolidated Statements of Comprehensive Income - 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	$ 132,660	$ 110,143	$ 420,726	$ 320,943
Other comprehensive income (loss), net of tax:
Net change in unrealized (losses) gains on available-for-sale investment securities	(1,906)	(4,907)	7,916	12,993
Foreign currency translation adjustments	3,870	(555)	8,013	(5,226)
Other comprehensive income (loss)	1,964	(5,462)	15,929	7,767
COMPREHENSIVE INCOME	$ 134,624	$ 104,681	$ 436,655	$ 328,710

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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