Accumulated Other Comprehensive Income (AOCI) (Details) $ in Millions	3 Months Ended
	Mar. 31, 2021 USD ($)
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance of Accumulated Other Comprehensive Income (Loss) at Beginning of Period	$ (2,604)
Other comprehensive income (loss) before reclassifications	247
Other Comprehensive Income (Loss), Net Investment Hedge, Gain (Loss), before Reclassification and Tax	230
Amounts reclassified from AOCI	(65)
Other comprehensive income (loss), tax, portion attributable to parent	(86)
Other Comprehensive Income (Loss), Net of Tax	326
Balance of Accumulated Other Comprehensive Income (Loss) at End of period	(2,278)
Foreign Currency Translation Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance of Accumulated Other Comprehensive Income (Loss) at Beginning of Period	(2,424)
Other comprehensive income (loss) before reclassifications	64
Other Comprehensive Income (Loss), Net Investment Hedge, Gain (Loss), before Reclassification and Tax	230
Amounts reclassified from AOCI	0
Other comprehensive income (loss), tax, portion attributable to parent	(56)
Other Comprehensive Income (Loss), Net of Tax	238
Balance of Accumulated Other Comprehensive Income (Loss) at End of period	(2,186)
Deferred Gain (Loss) On Hedging Activities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance of Accumulated Other Comprehensive Income (Loss) at Beginning of Period	185
Other comprehensive income (loss) before reclassifications	176
Amounts reclassified from AOCI	(75)
Other comprehensive income (loss), tax, portion attributable to parent	(25)
Other Comprehensive Income (Loss), Net of Tax	76
Balance of Accumulated Other Comprehensive Income (Loss) at End of period	261
Pension Liability Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance of Accumulated Other Comprehensive Income (Loss) at Beginning of Period	(365)
Other comprehensive income (loss) before reclassifications	8
Amounts reclassified from AOCI	10
Other comprehensive income (loss), tax, portion attributable to parent	(5)
Other Comprehensive Income (Loss), Net of Tax	13
Balance of Accumulated Other Comprehensive Income (Loss) at End of period	(352)
Unrealized Gain (Loss) On Investments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance of Accumulated Other Comprehensive Income (Loss) at Beginning of Period	0
Other comprehensive income (loss) before reclassifications	(1)
Amounts reclassified from AOCI	0
Other comprehensive income (loss), tax, portion attributable to parent	0
Other Comprehensive Income (Loss), Net of Tax	(1)
Balance of Accumulated Other Comprehensive Income (Loss) at End of period	$ (1)