Name:	all_OtherThanTemporaryImpairmentChangeInCreditLossesRecognizedInEarningsDueToAccretionInCashFlowsAndTimeValueOfCashFlows
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This item represents a decrease to the cumulative amount of credit losses recognized in earnings for a debt security that was written down to fair value during the period.

No definition available.

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- References

No definition available.

Name:	all_OtherThanTemporaryImpairmentLossesIncludedInAccumulatedOtherComprehensiveIncomeLineItems
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The pre-tax amount of other than temporary impairment loss on debt securities related to factors other than credit losses when the entity does not intend to sell the security and it is not more likely than not that the entity will be required to sell the security before recovery of its amortized cost basis. Such amount is included in accumulated other comprehensive income, attributable to the parent entity.

No definition available.

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The net unrealized gain or loss related to changes in valuation of fixed income securities subsequent to the impairment measurement date for fixed income securities with other than temporary impairment losses recorded in accumulated other comprehensive income.

No definition available.

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- References

No definition available.

Name:	us-gaap_InvestmentsAbstract
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This item represents an increase to the cumulative amount of credit losses recognized in earnings for an other than temporary impairment (OTTI) of a debt security held for which a previous OTTI was recognized and the investor does not intend to sell the debt security and it is not more likely than not that the investor will be required to sell the debt security before recovery of its amortized cost basis.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27340-111563

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This item represents an increase to the cumulative amount of credit losses recognized in earnings for an other than temporary impairment (OTTI) of a debt security held for which no such other than temporary impairment (OTTI) was previously recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27340-111563

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The cumulative amount of credit losses recognized in earnings related to debt securities held for which a portion of an other than temporary impairment (OTTI) was recognized in other comprehensive income (a component of shareholders' equity).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27340-111563

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This item represents reductions in the cumulative amount of credit losses recognized in earnings for an other than temporary impairment (OTTI) of a debt security because of the sale of impaired securities during the period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27340-111563

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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