Derivative Financial Instruments - Gains and Losses (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Derivative Instruments, Gain (Loss)
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Cost, Interest expense, Selling, general and administrative, Other (income) and expense	Cost, Interest expense, Selling, general and administrative, Other (income) and expense
(Gains)/losses recognized on derivatives	$ 206	$ (156)
(Gains)/losses recognized in earnings attributable to risk being hedged	(29)	86
(Gains)/Losses Recognized in Earnings and Other Comprehensive Income - Recognized in OCI	289	(867)
(Gains)/Losses Recognized in Earnings and Other Comprehensive Income - Reclassified from AOCI	311	(350)
(Gains)/Losses Recognized in Earnings and Other Comprehensive Income - Amounts Excluded from Effectiveness Testing	10	0
Interest rate contracts | Cash Flow Hedging
Derivative Instruments, Gain (Loss)
(Gains)/Losses Recognized in Earnings and Other Comprehensive Income - Recognized in OCI - Cash flow hedges	0	0
Foreign exchange contracts | Not Designated as Hedging Instrument, Economic Hedge
Derivative Instruments, Gain (Loss)
(Gains)/losses recognized on derivatives	103	(120)
Foreign exchange contracts | Cash Flow Hedging
Derivative Instruments, Gain (Loss)
(Gains)/Losses Recognized in Earnings and Other Comprehensive Income - Recognized in OCI - Cash flow hedges	(129)	42
(Gains)/Losses Recognized in Earnings and Other Comprehensive Income - Recognized in OCI - Amount excluded from the assessment of effectiveness	(46)	(101)
(Gains)/Losses Recognized in Earnings and Other Comprehensive Income - Amounts Excluded from Effectiveness Testing	32	26
Foreign exchange contracts | Net Investment Hedging
Derivative Instruments, Gain (Loss)
(Gains)/Losses Recognized in Earnings and Other Comprehensive Income - Recognized in OCI - Amount excluded from the assessment of effectiveness	14	12
(Gains)/Losses Recognized in Earnings and Other Comprehensive Income - Recognized in OCI - Net investment hedges	450	(820)
Equity contracts | Not Designated as Hedging Instrument, Economic Hedge
Derivative Instruments, Gain (Loss)
(Gains)/losses recognized on derivatives	66	34
Cost of financing | Interest rate contracts | Fair Value Hedging
Derivative Instruments, Gain (Loss)
(Gains)/losses recognized on derivatives	7	(11)
(Gains)/losses recognized in earnings attributable to risk being hedged	(5)	14
Cost of financing | Interest rate contracts | Cash Flow Hedging
Derivative Instruments, Gain (Loss)
(Gains)/Losses Recognized in Earnings and Other Comprehensive Income - Reclassified from AOCI	1	1
Cost of financing | Foreign exchange contracts | Cash Flow Hedging
Derivative Instruments, Gain (Loss)
(Gains)/Losses Recognized in Earnings and Other Comprehensive Income - Reclassified from AOCI	1	1
Cost of financing | Foreign exchange contracts | Net Investment Hedging
Derivative Instruments, Gain (Loss)
(Gains)/Losses Recognized in Earnings and Other Comprehensive Income - Amounts Excluded from Effectiveness Testing	(4)	(4)
Interest expense | Interest rate contracts | Fair Value Hedging
Derivative Instruments, Gain (Loss)
(Gains)/losses recognized on derivatives	30	(59)
(Gains)/losses recognized in earnings attributable to risk being hedged	(23)	72
Interest expense | Interest rate contracts | Cash Flow Hedging
Derivative Instruments, Gain (Loss)
(Gains)/Losses Recognized in Earnings and Other Comprehensive Income - Reclassified from AOCI	3	3
Interest expense | Foreign exchange contracts | Cash Flow Hedging
Derivative Instruments, Gain (Loss)
(Gains)/Losses Recognized in Earnings and Other Comprehensive Income - Reclassified from AOCI	3	3
Interest expense | Foreign exchange contracts | Net Investment Hedging
Derivative Instruments, Gain (Loss)
(Gains)/Losses Recognized in Earnings and Other Comprehensive Income - Amounts Excluded from Effectiveness Testing	(18)	(22)
Cost of services | Foreign exchange contracts | Cash Flow Hedging
Derivative Instruments, Gain (Loss)
(Gains)/Losses Recognized in Earnings and Other Comprehensive Income - Reclassified from AOCI	15	2
Cost of sales | Foreign exchange contracts | Cash Flow Hedging
Derivative Instruments, Gain (Loss)
(Gains)/Losses Recognized in Earnings and Other Comprehensive Income - Reclassified from AOCI	(1)	(8)
SG&A expense | Foreign exchange contracts | Cash Flow Hedging
Derivative Instruments, Gain (Loss)
(Gains)/Losses Recognized in Earnings and Other Comprehensive Income - Reclassified from AOCI	1	(3)
Other (income) and expense | Foreign exchange contracts | Cash Flow Hedging
Derivative Instruments, Gain (Loss)
(Gains)/Losses Recognized in Earnings and Other Comprehensive Income - Reclassified from AOCI	$ 289	$ (348)