Derivative Financial Instruments - Gains and Losses (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Derivative Instruments, Gain (Loss)
Gain (loss) recognized in earnings on derivatives	$ (514)	$ 3	$ (1,336)	$ 59
Gain (loss) recognized in earnings attributable to risk being hedged	271	15	395	55
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Recognized in OCI	1,387	587	3,567	1,470
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Reclassified from AOCI	12	(32)	(4)	(282)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Amounts Excluded from Effectiveness Testing	19	5	28	15
Foreign exchange contracts \| Derivative instruments in cash flow hedges
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Recognized in OCI	189	109	449	262
Foreign exchange contracts \| Instruments in net investment hedges
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Recognized in OCI	1,198	477	3,118	1,207
Foreign exchange contracts \| Not designated as hedging instruments - economic hedges
Derivative Instruments, Gain (Loss)
Gain (loss) recognized in earnings on derivatives	$ (186)	$ 15	$ (595)	$ (59)
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
Equity contracts \| Not designated as hedging instruments - economic hedges
Derivative Instruments, Gain (Loss)
Gain (loss) recognized in earnings on derivatives		$ (13)		$ 120
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 services \| Foreign exchange contracts \| Derivative instruments in cash flow hedges
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Reclassified from AOCI	$ 4	$ 12	$ 32	$ 33
Cost of sales \| Foreign exchange contracts \| Derivative instruments in cash flow hedges
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Reclassified from AOCI	35	1	71	(30)
Cost of financing \| Interest rate contracts \| Derivative instruments in fair value hedges
Derivative Instruments, Gain (Loss)
Gain (loss) recognized in earnings on derivatives	(64)	0	(76)	0
Gain (loss) recognized in earnings attributable to risk being hedged	68	4	89	15
Cost of financing \| Interest rate contracts \| Derivative instruments in cash flow hedges
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Reclassified from AOCI	(1)	(1)	(3)	(4)
Cost of financing \| Foreign exchange contracts \| Derivative instruments in cash flow hedges
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Reclassified from AOCI	(6)	(5)	(16)	(14)
Cost of financing \| Foreign exchange contracts \| Instruments in net investment hedges
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Amounts Excluded from Effectiveness Testing	5	1	6	4
SG&A expense \| Foreign exchange contracts \| Derivative instruments in cash flow hedges
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Reclassified from AOCI	8	(1)	28	(32)
SG&A expense \| Equity contracts \| Not designated as hedging instruments - economic hedges
Derivative Instruments, Gain (Loss)
Gain (loss) recognized in earnings on derivatives	(76)		(319)
Other (income) and expenses \| Foreign exchange contracts \| Derivative instruments in cash flow hedges
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Reclassified from AOCI	(6)	(22)	(51)	(187)
Other (income) and expenses \| Equity contracts \| Not designated as hedging instruments - economic hedges
Derivative Instruments, Gain (Loss)
Gain (loss) recognized in earnings on derivatives	3		(85)
Interest expense \| Interest rate contracts \| Derivative instruments in fair value hedges
Derivative Instruments, Gain (Loss)
Gain (loss) recognized in earnings on derivatives	(191)	0	(261)	(1)
Gain (loss) recognized in earnings attributable to risk being hedged	203	11	305	40
Interest expense \| Interest rate contracts \| Derivative instruments in cash flow hedges
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Reclassified from AOCI	(3)	(3)	(10)	(10)
Interest expense \| Foreign exchange contracts \| Derivative instruments in cash flow hedges
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Reclassified from AOCI	(18)	(13)	(54)	(38)
Interest expense \| Foreign exchange contracts \| Instruments in net investment hedges
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Amounts Excluded from Effectiveness Testing	$ 14	$ 3	$ 22	$ 11

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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-Publisher FASB
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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/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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-Publisher FASB
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Indicates line item in statement of income or comprehensive income that includes gain (loss) from derivative.

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