Consolidated Statement of Comprehensive Income (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Statement of Comprehensive Income [Abstract]
Net income	$ 251,723us-gaap_NetIncomeLoss	$ 339,523us-gaap_NetIncomeLoss	$ 352,547us-gaap_NetIncomeLoss
Other comprehensive (loss) income:
Change in foreign currency translation adjustment	(21,804)	8,482	2,457
Available for sale securities:
Change in net unrealized gains	(911)	(985)	3,603
Less: reclassification adjustment for net gains included in net income	(1,317)	(203)	(3,443)
Net change (net of tax effect)	(2,228)	(1,188)	160
(Loss) gain on pension liability	(6,512)	2,500	(3,925)
Cash flow hedges:
Change in unrealized gains	(9,074)	(67)	(653)
Less: reclassification adjustment for net (gains) losses included in net income	(2,123)	2,929	5,817
Net change (net of tax effect)	(11,197)	2,862	5,164
Other comprehensive (loss) income	(41,741)	12,656	3,856
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	$ 209,982us-gaap_ComprehensiveIncomeNetOfTax	$ 352,179us-gaap_ComprehensiveIncomeNetOfTax	$ 356,403us-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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