CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
Net income, as reported	$ 216,050	$ 177,980
Other comprehensive income:
Change in foreign currency translation adjustment	2,723	1,201
Available-for-sale investments:
Change in net unrealized gains	215	131
Net change in available-for-sale investments	215	131
Other comprehensive income	2,938	1,332
Comprehensive income	$ 218,988	$ 179,312

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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Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders.

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Amount after tax and reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities, attributable to parent entity. Excludes amounts related to other than temporary impairment (OTTI) loss.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature, attributable to parent entity.

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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

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