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Represents the number of reinstatements each year for each contract.

No definition available.

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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.

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

No definition available.

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Catastrophe Reinsurance Agreement Contract, Number Of Terms

No definition available.

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Represents the period of catastrophe reinsurance agreement contract.

No definition available.

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Represents the retention amount of catastrophe reinsurance agreement contracts.

No definition available.

Name:	all_CatastropheReinsuranceAgreementContractsRetentionAmount
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Data Type:	xbrli:monetaryItemType
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Catastrophe Reinsurance Loss Amount

No definition available.

Name:	all_CatastropheReinsuranceLossAmount
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Catastrophe Reinsurance, Remaining Available Limit Per Contract Year

No definition available.

Name:	all_CatastropheReinsuranceRemainingAvailableLimitPerContractYear
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Data Type:	xbrli:monetaryItemType
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Represents the amount of reinsurance ceded under various contracts.

No definition available.

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

Represents the number of reinsurance contracts under the agreement.

No definition available.

Name:	all_ReinsuranceContractsNumber
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Data Type:	xbrli:integerItemType
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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.

No definition available.

Name:	us-gaap_CededCreditRiskLineItems
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The charge against earnings in the period for the uninsured portion of a loss from a fire, explosion, or natural disaster (hurricane, earthquake).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.9)
-URI http://asc.fasb.org/extlink&oid=123367319&loc=SL114868664-224227

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