Condensed Consolidated Statements of Comprehensive Income (Unuaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Statement of Comprehensive Income [Abstract]
Net income	$ 28,887us-gaap_NetIncomeLoss	$ 55,939us-gaap_NetIncomeLoss
Other comprehensive income (loss):
Change in foreign currency translation adjustment	0	(721)
Available for sale securities:
Change in net unrealized gains	2,194	160
Less: reclassification adjustment for net losses (gains) included in net income	68	(163)
Net change (net of tax effect)	2,262	(3)
Cash flow hedges:
Change in unrealized (losses) gains	(5,691)	1,320
Less: reclassification adjustment for net losses (gains) included in net income	4,247	(1,297)
Net change (net of tax effect)	(1,444)	23
Other comprehensive income (loss)	818	(701)
Comprehensive income	$ 29,705us-gaap_ComprehensiveIncomeNetOfTax	$ 55,238us-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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