Reinsurance and Indemnification - Reinsurance recoverables on paid and unpaid benefits (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Reinsurance Retention Policy [Line Items]
Recoverables	$ 7,033
Reinsurance and indemnification recoverables, net	$ 9,220	$ 9,211
A- \| Reinsurer Concentration Risk
Reinsurance Retention Policy [Line Items]
Concentration risk, percentage	94.00%	93.00%
Property and casualty
Reinsurance Retention Policy [Line Items]
Paid	$ 101	$ 112
Recoverables	7,033	6,912
Reinsurance and indemnification recoverables, net	7,134	7,024
Allstate Annuities
Reinsurance Retention Policy [Line Items]
Reinsurance and indemnification recoverables, net	1,293	1,305
Allstate Life
Reinsurance Retention Policy [Line Items]
Reinsurance and indemnification recoverables, net	712	794
Allstate Benefits
Reinsurance Retention Policy [Line Items]
Reinsurance and indemnification recoverables, net	$ 81	$ 88

Reinsurance And Indemnification Recoverables, Net

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

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- Definition

Amount, after valuation allowance, recoverable under reinsurance contracts for losses reported to the ceding insurer but not yet paid and amounts expected for incurred losses and settlement expenses, which have not yet been reported to the ceding insurer.

+ References

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Amount, after valuation allowance, recoverable under reinsurance contracts for losses reported to and paid by the ceding insurer.

+ References

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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.

+ References

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