Comprehensive Income (Reclassifications out of Accumulated Other Comprehensive Loss) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015		Mar. 31, 2014
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Unrealized net losses on available-for-sale securities	$ (7,849)		$ (5,219)
Unrealized net losses on cash flow hedges	(576,464)		(544,606)
Net income	28,887		55,939
Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net income	4,315
Unrealized Gain on Available-for-sale Securities [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Unrealized net losses on available-for-sale securities	68
Unrealized Gain on Derivative Instruments [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Unrealized net losses on cash flow hedges	$ 4,247	[1]

[1] * Operating expenses amounts allocated to Research and development, Sales, marketing and services, and General and administrative are not individually significant.