Earnings Per Share (Schedule of Earnings Per Share, Basic and Diluted) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Class of Stock [Line Items]
Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent									$ (413)	$ 43	$ 302
Weighted Average Number of Shares Outstanding, Basic (in shares)									666	665	664
Income (Loss) from Continuing Operations, Per Basic Share	$ (0.95)	$ 0.52	$ 0.03	$ (0.22)	$ 0.48	$ (0.50)	$ (0.13)	$ 0.22	$ (0.62)	$ 0.06	$ 0.46
Net Income (Loss) from Continuing Operations Available to Common Shareholders, Diluted									$ (413)	$ 43	$ 302
Weighted Average Number of Shares Outstanding, Diluted (in shares)									666	668	667
Income (Loss) from Continuing Operations, Per Diluted Share	$ (0.95)	$ 0.48	$ 0.03	$ (0.22)	$ 0.47	$ (0.50)	$ (0.13)	$ 0.22	$ (0.62)	$ 0.06	$ 0.45
Share-based Payment Arrangement, Option [Member]
Class of Stock [Line Items]
Dilutive Securities, Effect on Basic Earnings Per Share, Options and Restrictive Stock Units									$ 0	$ 0	$ 0
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements (in shares)									0	1	0
Dilutive Securities Effect On Basic EPS, dilutive Stock Options, per diluted share									$ 0	$ 0	$ 0
Restricted Stock Units (RSUs) [Member]
Class of Stock [Line Items]
Dilutive Securities, Effect on Basic Earnings Per Share, Options and Restrictive Stock Units									$ 0	$ 0	$ 0
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements (in shares)									0	2	3
Dilutive Securities Effect On Basic EPS, dilutive Restricted Stock Units, per diluted share									$ 0	$ 0	$ (0.01)