Earnings (Loss) Per Share (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Earnings Per Share [Abstract]
Incremental common shares attributable to dilutive effect of share-based payment arrangements (in shares)	620,000	1,000,000	730,000	920,000
Antidilutive securities excluded from computation of earnings (in shares)	9,000	1,000	9,000	3,000
Treasury stock, shares, acquired (in shares)			435,376	415,695
Purchase of treasury stock			$ 18	$ 18