Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2014	Jun. 30, 2014
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 15,010us-gaap_NetIncomeLoss	$ (6,595)us-gaap_NetIncomeLoss
Other comprehensive income (loss) :
Foreign currency translation adjustments	(25,955)	(19,336)
Derivative adjustments
Fair valuation of derivatives	8,002	6,201
Reclassification adjustment for gain on derivatives included in net income (loss)	(2,647)	(2,644)
Investment adjustments
Unrealized gain on investments	925	1,201
Reclassification adjustment for gain on investments included in net income (loss)	(1,882)	(1,882)
Total comprehensive loss	$ (6,547)us-gaap_ComprehensiveIncomeNetOfTax	$ (23,055)us-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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Amount after tax and reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (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.

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Amount after tax of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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

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