Comprehensive Income (Reclassifications out of Accumulated Other Comprehensive Loss) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended			6 Months Ended
	Jun. 30, 2013		Jun. 30, 2012	Jun. 30, 2013		Jun. 30, 2012
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Unrealized net gains on available-for-sale securities	$ (646)		$ 525	$ (1,412)		$ 1,247
Unrealized net losses on cash flow hedges	527,256		438,660	1,028,633		861,062
Net income	64,461		92,006	124,149		160,273
Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Net income	(1,842)			(2,281)
Unrealized net gains on available-for-sale securities [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Unrealized net gains on available-for-sale securities	(54)			31
Unrealized net losses on cash flow hedges [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Unrealized net losses on cash flow hedges	$ (1,788)	[1]		$ (2,312)	[1]

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