Name:	all_CatastropheInsuranceAnnualCoverageLimitRetentionPercentage
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The limit of aggregated losses per contract year beyond which coverage provided by an aggregate excess agreement applies.

No definition available.

Name:	all_CatastropheReinsuranceAggregateLossLimitPerContractYear
Namespace Prefix:	all_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Catastrophe Reinsurance Aggregate Loss Limit Per Contract Year, In Excess of Layers

No definition available.

Name:	all_CatastropheReinsuranceAggregateLossLimitPerContractYearInExcessofLayers
Namespace Prefix:	all_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Represents the retention amount of catastrophe reinsurance agreement contracts.

No definition available.

Name:	all_CatastropheReinsuranceAgreementContractsRetentionAmount
Namespace Prefix:	all_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Represents the number of reinsurance contracts under the agreement.

No definition available.

Name:	all_ReinsuranceContractsNumber
Namespace Prefix:	all_
Data Type:	xbrli:integerItemType
Balance Type:	na
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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.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479838/944-20-50-3

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