Earnings (Loss) Per Share (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Earnings Per Share [Abstract]
Incremental common shares attributable to dilutive effect of share-based payment arrangements (in shares)	1,015,000	971,000
Antidilutive securities excluded from computation of earnings (in shares)		0
Treasury stock, shares, acquired (in shares)	435,376	317,508
Purchase of treasury stock	$ 18	$ 14