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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Contractual interest rate for funds borrowed, under the debt agreement.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Schedule II - Condensed Financial Information of Registrant - Narrative (Details) - USD ($) $ in Millions				12 Months Ended
	Jun. 09, 2023	Jun. 17, 2022	Apr. 05, 2021	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Jun. 18, 2021	Mar. 01, 2021
Condensed Financial Information of Registrant
Interest paid on debt				$ 355	$ 323	$ 321
Allstate Corporation
Condensed Financial Information of Registrant
Notes due to subsidiaries				0	1,000
Repayment of notes due to subsidiaries				1,000	1,000	2,450
Interest paid on debt				$ 355	$ 323	$ 321
Kennett Capital Inc \| Subsidiaries \| Allstate Corporation
Condensed Financial Information of Registrant
Notes due to subsidiaries		$ 1,000					$ 1,000	$ 200
Note stated interest rate (as a percent)		1.63%					0.20%	0.21%
Repayment of notes due to subsidiaries	$ 1,000	$ 1,000
Kennett Capital Inc, Second Repayment \| Subsidiaries \| Allstate Corporation
Condensed Financial Information of Registrant
Repayment of notes due to subsidiaries			$ 200