Derivative Financial Instruments - Gains and Losses (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Derivative Instruments, Gain (Loss)
Gain (loss) recognized in earnings on derivatives	$ (337)	$ (645)	$ (206)	$ (821)
Gain (loss) recognized in earnings attributable to risk being hedged	155	104	71	123
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Recognized in OCI	313	1,579	61	2,180
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Reclassified from AOCI	30	(16)	152	(16)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Amounts Excluded from Effectiveness Testing	32	6	60	9
Interest rate contracts \| Cash Flow Hedging
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Recognized in OCI	0	0	0	0
Foreign exchange contracts \| Cash Flow Hedging
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Recognized in OCI	178	200	149	260
Foreign exchange contracts \| Net Investment Hedging
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Recognized in OCI	$ 136	$ 1,379	$ (88)	$ 1,920
Foreign exchange contracts \| Not Designated as Hedging Instrument, Economic Hedge
Derivative Instruments, Gain (Loss)
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Other (income) and expense	Other (income) and expense	Other (income) and expense	Other (income) and expense
Gain (loss) recognized in earnings on derivatives	$ (196)	$ (313)	$ (180)	$ (409)
Equity contracts \| Not Designated as Hedging Instrument, Economic Hedge
Derivative Instruments, Gain (Loss)
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Selling, general and administrative	Selling, general and administrative	Selling, general and administrative	Selling, general and administrative
Cost of financing \| Interest rate contracts \| Fair Value Hedging
Derivative Instruments, Gain (Loss)
Gain (loss) recognized in earnings on derivatives	$ (30)	$ (17)	$ (21)	$ (18)
Gain (loss) recognized in earnings attributable to risk being hedged	25	23	13	26
Cost of financing \| Interest rate contracts \| Cash Flow Hedging
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Reclassified from AOCI	(1)	(1)	(2)	(2)
Cost of financing \| Foreign exchange contracts \| Cash Flow Hedging
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Reclassified from AOCI	(3)	(5)	(8)	(10)
Cost of financing \| Foreign exchange contracts \| Net Investment Hedging
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Amounts Excluded from Effectiveness Testing	5	1	11	2
Interest expense \| Interest rate contracts \| Fair Value Hedging
Derivative Instruments, Gain (Loss)
Gain (loss) recognized in earnings on derivatives	(153)	(61)	(96)	(65)
Gain (loss) recognized in earnings attributable to risk being hedged	130	81	58	97
Interest expense \| Interest rate contracts \| Cash Flow Hedging
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Reclassified from AOCI	(4)	(3)	(7)	(7)
Interest expense \| Foreign exchange contracts \| Cash Flow Hedging
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Reclassified from AOCI	(18)	(19)	(35)	(36)
Interest expense \| Foreign exchange contracts \| Net Investment Hedging
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Amounts Excluded from Effectiveness Testing	27	5	49	7
Cost of services \| Foreign exchange contracts \| Cash Flow Hedging
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Reclassified from AOCI	(3)	13	(5)	28
Cost of sales \| Foreign exchange contracts \| Cash Flow Hedging
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Reclassified from AOCI	2	23	17	35
SG&A expense \| Foreign exchange contracts \| Cash Flow Hedging
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Reclassified from AOCI	1	14	10	20
SG&A expense \| Equity contracts \| Not Designated as Hedging Instrument, Economic Hedge
Derivative Instruments, Gain (Loss)
Gain (loss) recognized in earnings on derivatives	42	(166)	91	(243)
Other (income) and expense \| Foreign exchange contracts \| Cash Flow Hedging
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Reclassified from AOCI	55	(38)	181	(45)
Other (income) and expense \| Equity contracts \| Not Designated as Hedging Instrument, Economic Hedge
Derivative Instruments, Gain (Loss)
Gain (loss) recognized in earnings on derivatives	$ 0	$ (88)	$ 0	$ (88)

Amount of the increase (decrease) in fair value of the hedged item in a fair value hedge recognized in the income statement.

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Amount of gain (loss) from excluded component of derivative hedge, recognized in earnings. Excludes recognition under systematic and rational method.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
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Indicates line item in statement of income or comprehensive income that includes gain (loss) from derivative.

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Amount before tax and reclassification adjustments of other comprehensive income (loss) attributable to parent.

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