CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
Net income, as reported	$ 141,003	$ 106,873	$ 236,254	$ 170,369
Other comprehensive income (loss):
Change in foreign currency translation adjustment	510	(2,441)	612	(3,533)
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 income (loss)	510	(2,441)	612	(5,058)
Comprehensive income	$ 141,513	$ 104,432	$ 236,866	$ 165,311

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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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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