Derivative Financial Instruments (Offsetting Assets and Liabilities) (Detail) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022
Derivative [Line Items]
Derivative Liability, Subject to Master Netting Arrangement, before Offset of Collateral, Total	$ 3	$ 2
Assets
Derivative [Line Items]
Gross assets presented 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
Derivative Liability, Subject to Master Netting Arrangement, before Offset of Collateral, Total	0	1
Assets \| Interest Rate Contract [Member] \| Over The Counter [Member]
Derivative [Line Items]
Gross assets presented 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
Derivative Liability, Subject to Master Netting Arrangement, before Offset of Collateral, Total	0	1
Liability
Derivative [Line Items]
Gross liabilities presented in the consolidated balance sheet	3	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	1	1
Gross amounts not offset in the consolidated balance sheet, net amounts	2	1
Liability \| Interest Rate Contract [Member] \| Over The Counter [Member]
Derivative [Line Items]
Gross liabilities presented in the consolidated balance sheet	3	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	1	1
Gross amounts not offset in the consolidated balance sheet, net amounts	$ 2	$ 1

Fair value of liability associated with 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.

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

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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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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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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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