Derivative Financial Instruments (Offsetting Assets and Liabilities) (Detail) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Derivative [Line Items]
Gross amounts not offset in the consolidated balance sheet, net amounts	$ 4	$ 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
Gross amounts not offset in the consolidated balance sheet, net amounts	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
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	1	1
Gross amounts not offset in the consolidated balance sheet, net amounts	3	1
Liability \| Interest Rate Contract [Member] \| Over The Counter [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	1	1
Gross amounts not offset in the consolidated balance sheet, net amounts	$ 3	$ 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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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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