Derivative Financial Instruments - Gains and Losses (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Derivative Instruments, Gain (Loss)
Gain (loss) recognized in earnings on derivatives	$ (645)	$ 54	$ (821)	$ 57
Gain (loss) recognized in earnings attributable to risk being hedged	104	15	123	40
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Recognized in OCI	1,579	(211)	2,180	883
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Reclassified from AOCI	(16)	(90)	(16)	(251)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Amounts Excluded from Effectiveness Testing	6	5	9	11
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	200	(34)	260	153
Foreign exchange contracts \| Instruments in net investment hedges
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Recognized in OCI	1,379	(177)	1,920	730
Foreign exchange contracts \| Not designated as hedging instruments - economic hedges
Derivative Instruments, Gain (Loss)
Gain (loss) recognized in earnings on derivatives	$ (313)	$ (30)	$ (409)	$ (74)
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		$ 83		$ 133
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]		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	$ 13	$ 7	$ 28	$ 21
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	23	(10)	35	(32)
Cost of financing \| Interest rate contracts \| Derivative instruments in fair value hedges
Derivative Instruments, Gain (Loss)
Gain (loss) recognized in earnings on derivatives	(17)	0	(18)	0
Gain (loss) recognized in earnings attributable to risk being hedged	23	4	26	11
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)	(2)	(2)
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	(5)	(5)	(10)	(9)
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	1	1	2	3
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	14	(16)	20	(31)
SG&A expense \| Equity contracts \| Not designated as hedging instruments - economic hedges
Derivative Instruments, Gain (Loss)
Gain (loss) recognized in earnings on derivatives	(166)		(243)
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	(38)	(49)	(45)	(165)
Other (income) and expenses \| Equity contracts \| Not designated as hedging instruments - economic hedges
Derivative Instruments, Gain (Loss)
Gain (loss) recognized in earnings on derivatives	(88)		(88)
Interest expense \| Interest rate contracts \| Derivative instruments in fair value hedges
Derivative Instruments, Gain (Loss)
Gain (loss) recognized in earnings on derivatives	(61)	0	(65)	(1)
Gain (loss) recognized in earnings attributable to risk being hedged	81	11	97	29
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)	(7)	(6)
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	(19)	(12)	(36)	(25)
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	$ 5	$ 4	$ 7	$ 8

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
-Topic 815
-SubTopic 20
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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

+ References

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-Publisher FASB
-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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