Financial Instruments - Cash Flow Hedges After-tax Gains/(Losses) (Details) - Cash flow hedges - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Derivative Instruments, Gain (Loss) [Line Items]
After-tax gains/(losses) reclassified from accumulated other comprehensive income into earnings/(losses)	$ (25)	$ (5)
After-tax gains/(losses) recognized in other comprehensive earnings/(losses)	27	(3)
Interest rate contracts
Derivative Instruments, Gain (Loss) [Line Items]
After-tax gains/(losses) reclassified from accumulated other comprehensive income into earnings/(losses)	(23)	(5)
After-tax gains/(losses) recognized in other comprehensive earnings/(losses)	25	(2)
Currency exchange contracts \| Forecasted transactions
Derivative Instruments, Gain (Loss) [Line Items]
After-tax gains/(losses) reclassified from accumulated other comprehensive income into earnings/(losses)	(2)	0
After-tax gains/(losses) recognized in other comprehensive earnings/(losses)	$ 2	$ (1)

Amount after tax, before reclassification adjustments of other comprehensive income (loss).

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