Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Tax Credit Carryforward [Line Items]
Deferred Tax Liabilities, Net	$ 19	$ 15
NOL allocated amount	3,400
AFG [Member]
Tax Credit Carryforward [Line Items]
NOL allocated amount	$ 1,640

Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences without jurisdictional netting.

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-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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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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