Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Net income	$ 82,620	$ 72,661
Other comprehensive income, net of tax:
Unrealized gain on marketable securities, available for sale		39
Total comprehensive income	$ 82,620	$ 72,700

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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-Section 45
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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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