Stockholders' Equity (Schedule of Components of Other Comprehensive Income (Loss), Net) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Comprehensive Income (Loss) [Line Items]
Foreign currency translation, gross amount	$ (4)	$ (10)	$ (65)
Foreign currency translation, income tax (provision) benefit	(4)	(6)	5
Foreign currency translation, net amount	(8)	(16)	(60)
Gain (loss) on cash flow hedges, gross amount	(26)	(38)	(12)
Gain (loss) on cash flow hedges, income tax (provision) benefit	8	8	2
Gain (loss) on cash flow hedges, net amount	(18)	(30)	(10)
Pension and postretirement benefits, gross amount	(2)	(6)	1
Pension and postretirement benefits, income tax (provision) benefit	0	(1)	(1)
Pension and postretirement benefits, net amount	(2)	(7)	0
Total other comprehensive income (loss), gross amount	(32)	(54)	(76)
Total other comprehensive income (loss), income tax (provision) benefit	4	1	6
Total other comprehensive income (loss), net of tax	$ (28)	$ (53)	$ (70)