Consolidated Statement of Comprehensive Income (Parenthetical) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Comprehensive Income [Abstract]
Tax provision (benefit) on currency translation adjustment	$ 25	$ 84	$ (145)
Tax benefit on unrealized holding losses on available-for-sale investments arising during the period	0	0	0
Tax provision on reclassification adjustment for gains on available-for-sale investments recognized in net income	0	0	1
Tax benefit on unrealized holding losses on hedging instruments arising during the period	12	0	0
Tax benefit on reclassification adjustment for losses on hedging instruments recognized in net income	6	3	5
Tax provision (benefit) on pension and other postretirement benefit liability adjustments arising during the period	(31)	2	7
Tax benefit on amortization of net loss and prior service benefit included in net periodic pension cost	$ 2	$ 5	$ 5