Financial Instruments, Derivatives and Hedging Activities - FV (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Carrying value
Fair value of assets and liabilities
Long-term debt	$ 1,700
Fair value
Fair value of assets and liabilities
Long-term debt	1,900
Fair Value, Measurements, Recurring
Fair value of assets and liabilities
Available for sale securities	12	$ 11
Derivative assets	68	69
Derivative liabilities	19	29
Long-term debt	1,919	1,751
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 1
Fair value of assets and liabilities
Available for sale securities	12	11
Derivative assets	53	53
Derivative liabilities	2	3
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 2
Fair value of assets and liabilities
Derivative assets	15	16
Derivative liabilities	17	26
Long-term debt	$ 1,919	$ 1,751

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.

+ References

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- Definition

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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-Name Accounting Standards Codification
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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