Derivative Financial Instruments (Offsetting Liabilities) (Detail) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Derivative [Line Items]
Gross liabilities presented in the consolidated balance sheet	$ 30	$ 19
Gross amounts not offset in the consolidated balance sheet, financial instruments	0	0
Gross amounts not offset in the consolidated balance sheet, cash collateral paid	21	19
Gross amounts not offset in the consolidated balance sheet, net amounts	9	0
Interest Rate Contract [Member] \| Over The Counter [Member]
Derivative [Line Items]
Gross liabilities presented in the consolidated balance sheet	30	19
Gross amounts not offset in the consolidated balance sheet, financial instruments	0	0
Gross amounts not offset in the consolidated balance sheet, cash collateral paid	21	19
Gross amounts not offset in the consolidated balance sheet, net amounts	$ 9	$ 0

Amount of right to receive cash collateral under master netting arrangements that have not been offset against derivative liabilities.

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Amount of right to receive securities collateral under master netting arrangements that have not been offset against derivative liabilities.

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- Definition

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 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 offset, deducted from derivative liabilities.

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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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