Accumulated Other Comprehensive Income (AOCI) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2021
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance of Accumulated Other Comprehensive Income (Loss) at Beginning of Period	$ (2,121)	$ (2,604)
Other comprehensive income (loss) before reclassifications	59	723
Other Comprehensive Income (Loss), Net Investment Hedge, Gain (Loss), before Reclassification and Tax	126	292
Amounts reclassified from AOCI	(114)	(345)
Other comprehensive income (loss), tax, portion attributable to parent	(26)	(142)
Other Comprehensive Income (Loss), Net of Tax	45	528
Balance of Accumulated Other Comprehensive Income (Loss) at End of period	(2,076)	(2,076)
Foreign Currency Translation Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance of Accumulated Other Comprehensive Income (Loss) at Beginning of Period	(2,143)	(2,424)
Other comprehensive income (loss) before reclassifications	(149)	14
Other Comprehensive Income (Loss), Net Investment Hedge, Gain (Loss), before Reclassification and Tax	126	292
Amounts reclassified from AOCI	0	0
Other comprehensive income (loss), tax, portion attributable to parent	(30)	(78)
Other Comprehensive Income (Loss), Net of Tax	(53)	228
Balance of Accumulated Other Comprehensive Income (Loss) at End of period	(2,196)	(2,196)
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	328	185
Other comprehensive income (loss) before reclassifications	197	693
Amounts reclassified from AOCI	(122)	(435)
Other comprehensive income (loss), tax, portion attributable to parent	(1)	(41)
Other Comprehensive Income (Loss), Net of Tax	74	217
Balance of Accumulated Other Comprehensive Income (Loss) at End of period	402	402
Pension Liability Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance of Accumulated Other Comprehensive Income (Loss) at Beginning of Period	(303)	(365)
Other comprehensive income (loss) before reclassifications	5	12
Amounts reclassified from AOCI	8	90
Other comprehensive income (loss), tax, portion attributable to parent	5	(22)
Other Comprehensive Income (Loss), Net of Tax	18	80
Balance of Accumulated Other Comprehensive Income (Loss) at End of period	(285)	(285)
Unrealized Gain (Loss) On Investments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance of Accumulated Other Comprehensive Income (Loss) at Beginning of Period	(3)	0
Other comprehensive income (loss) before reclassifications	6	4
Amounts reclassified from AOCI	0	0
Other comprehensive income (loss), tax, portion attributable to parent	0	(1)
Other Comprehensive Income (Loss), Net of Tax	6	3
Balance of Accumulated Other Comprehensive Income (Loss) at End of period	$ 3	$ 3