CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
Net income, as reported	$ 121,600	$ 92,187	$ 357,854	$ 262,555
Other comprehensive (loss) income:
Change in foreign currency translation adjustment	(5,716)	1,850	(5,104)	(1,683)
Available-for-sale investments:
Reclassification adjustment for net gains included in net income				(1,525)
Net change in available-for-sale investments				(1,525)
Other comprehensive (loss) income	(5,716)	1,850	(5,104)	(3,208)
Comprehensive income	$ 115,884	$ 94,037	$ 352,750	$ 259,347

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=6519514

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

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Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).

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

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