Accumulated Other Comprehensive Income (Summary of Amounts Reclassified Out of AOCI) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Reclassifications out of accumulated other comprehensive income (loss)
(Gains) losses on cash flow hedges	$ 31,556	$ 31,872	$ 97,205	$ 98,717
Income tax expense (benefit)	6,049	44,147	(16,706)	3,203
Total reclassifications of (income) loss, net of tax	(2,117)	(164,002)	62,425	(4,817)
Amounts reclassified from Accumulated Other Comprehensive Income (Loss)
Reclassifications out of accumulated other comprehensive income (loss)
Total reclassifications of (income) loss, net of tax	3,172	4,309	9,186	8,818
Accumulated Other Comprehensive Income (Loss) Components | Amounts reclassified from Accumulated Other Comprehensive Income (Loss)
Reclassifications out of accumulated other comprehensive income (loss)
(Gains) losses on cash flow hedges	4,060	5,233	11,749	10,743
Income tax expense (benefit)	$ (888)	$ (924)	$ (2,563)	$ (1,925)