Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 1,866,916	$ 1,211,242	$ 558,929
Other comprehensive income (loss):
Foreign currency translation adjustments	(3,939)	975	27,409
Change in unrealized gains (losses) on available-for-sale securities, net of tax of $0, $0, and $378, respectively	0	0	599
Total other comprehensive income (loss)	(3,939)	975	28,008
Comprehensive income	$ 1,862,977	$ 1,212,217	$ 586,937

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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