Guarantees and Contingent Liabilities (Details)	3 Months Ended
	Mar. 31, 2024 USD ($) claim	Nov. 11, 2016 officer
The Allstate Corp. Securities Litigation
Guarantor Obligations [Line Items]
Number of officers | officer		2
Holland Hewitt v. Allstate Life Insurance Company
Guarantor Obligations [Line Items]
Number of putative class actions | claim	2
Minimum
Guarantor Obligations [Line Items]
Loss contingencies, reasonably possible pretax loss exposure in excess of the amount accrued	$ 0
Maximum
Guarantor Obligations [Line Items]
Loss contingencies, reasonably possible pretax loss exposure in excess of the amount accrued	$ 87,000,000