Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Statement of Comprehensive Income [Abstract]
Net income	$ 23,696us-gaap_NetIncomeLoss	$ 53,115us-gaap_NetIncomeLoss
Other comprehensive income (loss):
Foreign currency translation adjustments	(39,490)	461
Change in unrealized gains on available-for-sale securities, net of tax of $133 and $291, respectively	782	467
Total other comprehensive (loss) income	(38,708)	928
Comprehensive (loss) income	$ (15,012)us-gaap_ComprehensiveIncomeNetOfTax	$ 54,043us-gaap_ComprehensiveIncomeNetOfTax

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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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 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, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities and unrealized holding gain (loss) related to transfers of securities into the available-for-sale classification and out of the held-to-maturity classification.

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

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