Accumulated Other Comprehensive Income (Schedule of Reclassifications out of AOCI) (Details) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2020	Sep. 30, 2019
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Cost of revenue	$ 299,183			$ 260,353			$ 824,179	$ 767,062
Tax expense	17,633			23,960			77,376	76,464
Gain (loss), net of tax	146,321	$ 148,996	$ 111,856	108,838	$ 125,701	$ 102,709	407,173	337,248
Accumulated Net Gain (Loss) from Cash Flow Hedges | Amount of (Loss) Gain Reclassified from Accumulated Other Comprehensive Income into Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Cost of revenue	(591)			3,171			2,562	7,091
Tax expense	(53)			688			526	1,295
Gain (loss), net of tax	$ (538)			$ 2,483			$ 2,036	$ 5,796