Derivative Financial Instruments (Offsetting Assets and Liabilities) (Detail) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Derivative [Line Items]
Gross amounts not offset in the consolidated balance sheet, cash collateral received	$ 0	$ 0
Gross liabilities presented in the consolidated balance sheet	4	2
Assets
Derivative [Line Items]
Assets not offset in the consolidated balance sheet	0	1
Gross amounts not offset in the consolidated balance sheet, financial instruments	0	0
Gross amounts not offset in the consolidated balance sheet, cash collateral received	0	0
Gross amounts not offset in the consolidated balance sheet, net amounts	0	1
Over The Counter [Member] \| Assets \| Interest Rate Contract [Member]
Derivative [Line Items]
Assets not offset in the consolidated balance sheet	0	1
Gross amounts not offset in the consolidated balance sheet, financial instruments	0	0
Gross amounts not offset in the consolidated balance sheet, cash collateral received	0	0
Gross amounts not offset in the consolidated balance sheet, net amounts	0	1
Liability
Derivative [Line Items]
Gross liabilities presented in the consolidated balance sheet	4	2
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	0	1
Gross amounts not offset in the consolidated balance sheet, net amounts	4	1
Liability \| Over The Counter [Member] \| Interest Rate Contract [Member]
Derivative [Line Items]
Gross liabilities presented in the consolidated balance sheet	4	2
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	0	1
Gross amounts not offset in the consolidated balance sheet, net amounts	$ 4	$ 1

Derivative asset, not subject to master netting arrangement, deduction, cash collateral received.

No definition available.

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- Definition

Fair value of 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, not subject to a master netting arrangement.

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- Definition

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- Definition

Amount of obligation to return cash collateral under master netting arrangements that have not been offset against derivative assets.

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- Definition

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

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- Definition

Fair value, after offset of derivative liability, of 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, before offset against an obligation to return collateral under a master netting arrangement. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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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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- Definition

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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Fair value, after effect of master netting arrangement and deduction of obligation to return financial collateral not offset and financial instrument subject to master netting arrangement not offset, of financial liability or contract with one or more underlyings, notional amount or payment provision or both, and contract can be net settled by means outside contract or delivery of asset. Excludes derivative not subject to master netting arrangement or similar agreement.

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- Definition

Fair value of financial liability or contract with one or more underlyings, notional amount or payment provision or both, and contract can be net settled by means outside contract or delivery of asset, subject to master netting arrangement or similar agreement and not elected or qualified to offset, deducted from derivative liability.

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- Definition

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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