Derivative Financial Instruments - Gains and Losses (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Derivative Instruments, Gain (Loss)
Gain (loss) recognized in earnings on derivatives	$ (176)	$ 3
Gain (loss) recognized in earnings attributable to risk being hedged	20	25
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Recognized in OCI	601	1,094
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Reclassified from AOCI	1	(160)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Amounts Excluded from Effectiveness Testing	3	6
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	60	187
Foreign exchange contracts \| Instruments in net investment hedges
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Recognized in OCI	541	907
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	15	14
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	12	(22)
Cost of financing \| Interest rate contracts \| Derivative instruments in fair value hedges
Derivative Instruments, Gain (Loss)
Gain (loss) recognized in earnings on derivatives	(1)	(1)
Gain (loss) recognized in earnings attributable to risk being hedged	4	7
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)
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)
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	2
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	6	(15)
SG&A expense \| Equity contracts \| Not designated as hedging instruments - economic hedges
Derivative Instruments, Gain (Loss)
Gain (loss) recognized in earnings on derivatives	(76)	49
Other (income) and 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	(7)	(116)
Other (income) and expense \| Foreign exchange contracts \| Not designated as hedging instruments - economic hedges
Derivative Instruments, Gain (Loss)
Gain (loss) recognized in earnings on derivatives	(95)	(44)
Interest expense \| Interest rate contracts \| Derivative instruments in fair value hedges
Derivative Instruments, Gain (Loss)
Gain (loss) recognized in earnings on derivatives	(4)	(1)
Gain (loss) recognized in earnings attributable to risk being hedged	16	18
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)
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	(17)	(13)
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	$ 2	$ 4

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
-Name Accounting Standards Codification
-Topic 815
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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.

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

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