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

Interest credited to contractholder funds which has been assumed and expensed during the period for life and annuity insurance contracts, as well as accident and health insurance contracts.

No definition available.

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

Premiums and contract charges related to life insurance, accident and health insurance and annuity contracts that are assumed and earned from another insurer as a result of reinsurance arrangements.

No definition available.

Name:	all_AssumedLifeAndAnnuityPremiumsAndContractCharges
Namespace Prefix:	all_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Premiums and contract charges related to life insurance, accident and health insurance and annuity contracts that are assumed and earned by another insurer as a result of reinsurance arrangements.

No definition available.

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

Name:	all_CostsNetOfReinsuranceRecoveriesLifeAbstract
Namespace Prefix:	all_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Contract benefits related to provision for benefits, claims and claims settlement expenses directly incurred during the period for life and annuity insurance contracts, as well as accident and health insurance contracts.

No definition available.

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

Interest credited to contractholder funds which has been directly incurred and expensed during the period for life and annuity insurance contracts, as well as accident and health insurance contracts.

No definition available.

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

Premiums and contract charges related to life insurance, accident and health insurance and annuity contracts that are written and earned directly by the insurer before adding contracts assumed from other insurers or subtracting any amounts assumed by other insurers.

No definition available.

Name:	all_DirectLifeAndAnnuityPremiumsAndContractCharges
Namespace Prefix:	all_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Provision for benefits, claims and claims settlement expenses incurred during the period for life and annuity insurance contracts, as well as accident and health insurance contracts, net of the effects of contracts assumed and ceded.

No definition available.

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

Premiums recognized as revenue in the period on all life insurance and reinsurance contracts, as well as accident and health insurance and reinsurance contracts, after subtracting any amounts ceded to another insurer. Also includes an amount that an insurer adds to a policy's premium, or deducts from a policy's cash value or contract holder's account, as compensation for services rendered (may include fees), after subtracting any amounts ceded to another insurer.

No definition available.

Name:	all_LifeAndAnnuityPremiumsAndContractChargesNetOfReinsuranceCeded
Namespace Prefix:	all_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

The amount in the period for estimated recoupment of interest credited expense under annuity contracts ceded.

No definition available.

Name:	all_ReinsuranceCededInterestCreditedToPolicyholdersAccountBalances
Namespace Prefix:	all_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

The amount in the period for estimated recoupment of contract benefits under life insurance, accident and health insurance, and annuity contracts ceded.

No definition available.

Name:	all_ReinsuranceCededLifeAndAnnuityContractBenefits
Namespace Prefix:	all_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

The percentage of reinsurance recoverables due from companies rated A- or better by Standard and Poor's.

No definition available.

Name:	all_ReinsuranceRecoverableStandardPoorsAMinusRatingPercent
Namespace Prefix:	all_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

Name:	all_RevenueNetOfReinsuranceRecoveriesLifeAbstract
Namespace Prefix:	all_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Name:	us-gaap_EffectsOfReinsuranceLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Interest allocated to policyholders holding contracts under which the insurer must provide a guaranteed yield.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-04.6)

-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 20

-Section 45

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6480726&loc=d3e6691-158385

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 6

-Article 7

Name:	us-gaap_InterestCreditedToPolicyholdersAccountBalances
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Name:	us-gaap_ReinsuranceReceivablesAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Amount after valuation allowance recoverable including premium paid under reinsurance contracts. Examples include, but are not limited to, settled and unsettled claims, incurred but not reported losses, loss adjustment expense, premium paid, policy benefits and policy reserves.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 6

-Article 7

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 20

-Section 50

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=6480758&loc=d3e6824-158387

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.(a),6)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Name:	us-gaap_ReinsuranceRecoverables
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Name:	dei_LegalEntityAxis=all_NonAffiliatesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	dei_LegalEntityAxis=us-gaap_AffiliatedEntityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis=us-gaap_AccidentAndHealthInsuranceSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis=us-gaap_InvestmentsSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis=us-gaap_LifeInsuranceSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: