Financial Instruments - Recurring fair value measurements (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Assets
Derivatives	$ 29	$ 118
Investment securities	1,041	1,532
Liabilities
Derivatives	(49)	(52)
Recurring
Assets
Derivatives	29	118
Investment securities	1,041	1,532
Assets, fair value	1,070	1,650
Liabilities
Derivatives	(49)	(52)
Total liabilities	(49)	(52)
Recurring \| Level 1
Assets
Derivatives	0	0
Investment securities	1,033	1,502
Assets, fair value	1,033	1,502
Liabilities
Derivatives	0	0
Total liabilities	0	0
Recurring \| Level 2
Assets
Derivatives	29	118
Investment securities	0	0
Assets, fair value	29	118
Liabilities
Derivatives	(49)	(52)
Total liabilities	(49)	(52)
Recurring \| Level 3
Assets
Derivatives	0	0
Investment securities	8	30
Assets, fair value	8	30
Liabilities
Derivatives	0	0
Total liabilities	$ 0	$ 0

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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Fair value of financial and nonfinancial obligations.

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