2.4.0.84070 - Disclosure - Guarantees and Contingent Liabilities (Details)truefalseIn Millions, unless otherwise specifiedfalse1false USDfalsefalse$I2013Q2_PaymentGuaranteeMemberhttp://www.sec.gov/CIK0000352736instant2013-06-30T00:00:000001-01-01T00:00:00USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$1false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse1false USDtruefalse$I2013Q2_PaymentGuaranteeMemberhttp://www.sec.gov/CIK0000352736instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseObligations of insolvent insurance companiesus-gaap_GuaranteeObligationsByNatureAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_PaymentGuaranteeMemberus-gaap_GuaranteeObligationsByNatureAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Obligations of insolvent insurance companies2true 3us-gaap_GuaranteeObligationsLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Guarantees and Contingent Liabilities3false 4us-gaap_GuaranteeObligationsMaximumExposureus-gaap_truecreditinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse40000004USD$falsetruefalsexbrli:monetaryItemTypemonetaryMaximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Interpretation (FIN) -Number 45 -Paragraph 13 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 460 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248 false2Maximum amount at risk pursuant to a guaranteefalseGuarantees and Contingent Liabilities (Details) (Obligations of insolvent insurance companies, USD $)MillionsUnKnownUnKnownUnKnowntruefalsefalseSheethttp://www.allstate.com/role/DisclosureGuaranteesAndContingentLiabilitiesDetails13