(Schedule of Unrecognized Tax Benefits Rollforward) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Balance at January 1	$ (189)	$ (220)	$ (188)
(Additions) reductions for tax positions related to current year	(10)	(5)	(7)
(Additions) for tax positions related to prior years	(10)	(6)	(37)
Reductions for tax positions related to prior years	30	5	5
Settlements	13	31	2
Expiration of statutes of limitations	1	3	2
Currency translation adjustment	(1)	(3)	(3)
Balance at December 31	$ (166)	$ (189)	$ (220)