2.4.0.84020 - Disclosure - Supplemental Cash Flow Information (Details)truefalseIn Millions, unless otherwise specifiedfalse1false USDfalsefalse$D2013Q2YTDhttp://www.sec.gov/CIK0000352736duration2013-01-01T00:00:002013-06-30T00:00:00USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$2false USDfalsefalse$D2012Q2YTDhttp://www.sec.gov/CIK0000352736duration2012-01-01T00:00:002012-06-30T00:00:00USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$1true 1us-gaap_SupplementalCashFlowInformationAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Supplemental Cash Flow Information2false 2us-gaap_TransferOfInvestmentsus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse191000000191USD$falsetruefalse2truefalsefalse9500000095USD$falsetruefalsexbrli:monetaryItemTypemonetaryValue of investments transferred from the entity's investments in noncash transactions.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4313-108586 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 32 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4332-108586 false2Non-cash modifications of certain mortgage loans, fixed income securities, limited partnerships and other investments, as well as mergers completed with equity securities3true 2alic_NetChangeInProceedsManagedAbstractalic_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Net change in proceeds managed4false 3alic_NetChangeInShortTermInvestmentsOfProceedsManagedCollateralalic_falsedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse115000000115falsefalsefalse2truefalsefalse-162000000-162falsefalsefalsexbrli:monetaryItemTypemonetaryThe net change in short-term investments from the proceeds managed related to collateral received in conjunction with the entity's securities lending and over-the-counter derivatives.No definition available.false2Net change in short-term investments5false 3alic_NetCashProvidedByUsedInOperatingActivitiesProceedsManagedCollateralalic_falsedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse115000000115falsefalsefalse2truefalsefalse-162000000-162falsefalsefalsexbrli:monetaryItemTypemonetaryThe net operating cash flow provided or used related to collateral received in conjunction with the entity's securities lending and over-the-counter derivatives.No definition available.false2Operating cash flow provided (used)6true 2alic_NetChangeInLiabilitiesForCollateralAbstractalic_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Net change in liabilities7false 3alic_ObligationToReturnCollateralSecuritiesLendingAndDerivativesalic_falsecreditinstantfalsefalsefalsefalsefalsetruefalsetruenegatedPeriodStartLabel1truefalsefalse-561000000-561falsefalsefalse2truefalsefalse-263000000-263falsefalsefalsexbrli:monetaryItemTypemonetaryThe liability to return cash and securities received as collateral in conjunction with securities lending and over-the-counter derivatives.No definition available.false2Liabilities for collateral, beginning of year8false 3alic_ObligationToReturnCollateralSecuritiesLendingAndDerivativesalic_falsecreditinstantfalsefalsefalsefalsefalsefalsetruetruenegatedPeriodEndLabel1truefalsefalse-446000000-446falsefalsefalse2truefalsefalse-425000000-425falsefalsefalsexbrli:monetaryItemTypemonetaryThe liability to return cash and securities received as collateral in conjunction with securities lending and over-the-counter derivatives.No definition available.false2Liabilities for collateral, end of period9false 3alic_NetCashProvidedByUsedInOperatingActivitiesLiabilitiesForCollateralalic_falsecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse-115000000-115USD$falsetruefalse2truefalsefalse162000000162USD$falsetruefalsexbrli:monetaryItemTypemonetaryThe net operating cash flow provided by (used in) the net change in liabilities for collateral.No definition available.false2Operating cash flow (used) providedfalseSupplemental Cash Flow Information (Details) (USD $)MillionsUnKnownUnKnownUnKnowntruefalsefalseSheethttp://www.allstate.com/role/DisclosureSupplementalCashFlowInformationDetails29