Guarantees and Contingent Liabilities (Details) $ in Millions	9 Months Ended
	Sep. 30, 2022 USD ($) claim
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	$ 178