Variable Interest Entities - Narrative (Details) - Variable Interest Entity, Primary Beneficiary - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Variable Interest Entity [Line Items]
Notes payable	$ 123		$ 123
Allstate Protection
Variable Interest Entity [Line Items]
Property and casualty insurance premiums	42	$ 45
Incurred expense (adjustment)	$ 34	$ 38

Amount, after effects of reinsurance, of expense (reversal of expense) for claims incurred and costs incurred in the claim settlement process.

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- Definition

Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

+ References

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- Definition

Amount, after premiums ceded to other entities and premiums assumed by the entity, of premiums earned.

+ References

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- Definition

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.

+ References

No definition available.

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