Financial Instruments - Recurring Fair Value Measurements (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Assets
Investment securities	$ 189	$ 283
Total assets	61	58
Liabilities
Total liabilities	(36)	(27)
Fair value, measurements, recurring
Assets
Derivatives	61	58
Investment securities	189	283
Total assets	250	341
Liabilities
Derivatives	(36)	(27)
Total liabilities	(36)	(27)
Fair value, measurements, recurring \| Level 1
Assets
Derivatives	0	0
Investment securities	2	24
Total assets	2	24
Liabilities
Derivatives	0	0
Total liabilities	0	0
Fair value, measurements, recurring \| Level 2
Assets
Derivatives	61	58
Investment securities	0	0
Total assets	61	58
Liabilities
Derivatives	(36)	(27)
Total liabilities	(36)	(27)
Fair value, measurements, recurring \| Level 3
Assets
Derivatives	0	0
Investment securities	187	259
Total assets	187	259
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, after the effects of master netting arrangements, of a financial liability or 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 liabilities 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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