Derivative Financial Instruments (Schedule of Offsetting Liabilities) (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Derivative Liabilities [Abstract]
Gross amount recognized	$ 67	$ 123
Gross amount offset in the consolidated balance sheets	1	2
Net amount presented in the consolidated balance sheets	66	121
Gross amount not offset in the consolidated balance sheets	8	11
Net amount	$ 58	$ 110

Fair value, before 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 elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Fair value, after offset of derivative asset, of 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, elected not to be and before offset against a right to receive collateral under a master netting arrangement. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Amount of right to receive cash collateral under master netting arrangements offset against derivative liabilities.

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Fair value of asset associated with 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.

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