Equity - AOCL (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Accumulated Other Comprehensive Loss
Balance at the beginning of the period	$ 2,951
Balance at the end of the period	2,637
Cumulative Translation Adjustment
Accumulated Other Comprehensive Loss
Balance at the beginning of the period	(1,114)	$ (1,089)
Other comprehensive (loss) gain before reclassification adjustments	(52)	(134)
Net other comprehensive income (loss)	(52)	(134)
Balance at the end of the period	(1,166)	(1,223)
Hedging Activities
Accumulated Other Comprehensive Loss
Balance at the beginning of the period	42	(9)
Other comprehensive (loss) gain before reclassification adjustments	29	(46)
(Gain) reclassified from accumulated OCL	(1)	6
Tax benefit (provision)	(7)	10
Net other comprehensive income (loss)	21	(30)
Balance at the end of the period	63	(39)
Pension and other postretirement plans
Accumulated Other Comprehensive Loss
Balance at the beginning of the period	(61)	(60)
Balance at the end of the period	(61)	(60)
Accumulated Other Comprehensive Loss
Accumulated Other Comprehensive Loss
Balance at the beginning of the period	(1,133)	(1,158)
Other comprehensive (loss) gain before reclassification adjustments	(23)	(180)
(Gain) reclassified from accumulated OCL	(1)	6
Tax benefit (provision)	(7)	10
Net other comprehensive income (loss)	(31)	(164)
Balance at the end of the period	$ (1,164)	$ (1,322)