XML 168 R149.htm IDEA: XBRL DOCUMENT
v3.19.1

Capital Structure - Narrative (Details) |  |  |  |  | 12 Months Ended
--- | --- | --- | --- | --- | ---
Oct. 15, 2018 USD ($) $ / shares shares | May 15, 2018 USD ($) | May 13, 2018 USD ($) | Mar. 29, 2018 USD ($) $ / shares shares | Dec. 31, 2018 USD ($) director $ / shares shares | Dec. 31, 2017 USD ($) $ / shares shares | Dec. 31, 2016 USD ($)
Class of Stock [Line Items] |  |  |  |  |  |  |
Repayments of Long-term Debt |  |  |  |  | $ 400,000,000 | $ 0 | $ 17,000,000
Long-term debt |  |  |  |  | 6,451,000,000 | 6,350,000,000 |
Unsecured revolving credit facility |  |  |  |  | 1,000,000,000.00 |  |
Commercial Paper maximum borrowing capacity |  |  |  |  | 1,000,000,000.00 |  |
Additional borrowing capacity under credit facility increase provision |  |  |  |  | $ 500,000,000 |  |
Maximum debt to capital ratio allowed under credit facility covenant (as a percent) |  |  |  |  | 37.50% |  |
Credit facility, amount outstanding |  |  |  |  | $ 0 | 0 |
Interest paid on debt |  |  |  |  | 330,000,000 | 332,000,000 | 287,000,000
Other liabilities and accrued expenses |  |  |  |  | $ 260,000,000 | $ 169,000,000 |
Common stock |  |  |  |  |  |  |
Common stock, shares issued (in shares) | shares |  |  |  |  | 900,000,000 | 900,000,000 |
Common stock, shares outstanding (in shares) | shares |  |  |  |  | 332,000,000 | 355,000,000 |
Treasury stock, shares (in shares) | shares |  |  |  |  | 568,000,000 | 545,000,000 |
Reacquired shares (in shares) | shares |  |  |  |  | 25,000,000 |  |
Average cost of reacquired shares (in dollars per share) | $ / shares |  |  |  |  | $ 88.07 |  |
Reissued net shares under equity incentive plans (in shares) | shares |  |  |  |  | 2,000,000 |  |
Preferred stock |  |  |  |  |  |  |
Preferred stock, par value (in dollars per share) | $ / shares |  |  |  |  | $ 1 | $ 1 |
Redemption of preferred stock |  |  |  |  | $ 385,000,000 | $ 0 | $ 0
Period of issuance of common stock prior to dividend declaration date during which dividend declaration is prohibited |  |  |  |  | 90 days |  |
Noncumulative Perpetual Preferred Stock |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |
Period after occurrence of certain tax and rating agency events in which redemption of debt in whole permissible |  |  |  |  | 90 days |  |
Preferred stock |  |  |  |  |  |  |
Stock Redeemed (in shares) | shares | 15,400 |  |  |  |  |  |
Preferred stock, par value (in dollars per share) | $ / shares | $ 1.00 |  |  | $ 1.00 | $ 1.00 |  |
Preferred stock, shares liquidation preference (in dollars per share) | $ / shares | $ 25,000 |  |  | $ 25,000 | 25,000 |  |
Redemption of preferred stock | $ 385,000,000 |  |  |  |  |  |
Stock issued during period (in shares) | shares |  |  |  | 23,000 |  |  |
Dividend rate |  |  |  | 5.625% |  |  |
Proceeds from issuance of redeemable preferred stock |  |  |  | $ 575,000,000 |  |  |
Preferred stock, redemption price (in dollars per share) | $ / shares |  |  |  |  | $ 25,000 |  |
Series E |  |  |  |  |  |  |
Preferred stock |  |  |  |  |  |  |
Dividend rate |  |  |  |  | 6.625% |  |
Series F |  |  |  |  |  |  |
Preferred stock |  |  |  |  |  |  |
Dividend rate |  |  |  |  | 6.25% |  |
Minimum |  |  |  |  |  |  |
Preferred stock |  |  |  |  |  |  |
Collective risk-based capital ratios of subsidiaries as a percentage of net written premiums of insurance business |  |  |  |  | 80.00% |  |
Percentage of decline in consolidated shareholders' equity from benchmark quarter |  |  |  |  | 20.00% |  |
Maximum |  |  |  |  |  |  |
Preferred stock |  |  |  |  |  |  |
Risk-based capital ratios as a percentage of action level risk-based capital |  |  |  |  | 175.00% |  |
Percentage by which consolidated shareholders' equity should increase or decrease to avoid restriction on dividends |  |  |  |  | 20.00% |  |
Maximum | Noncumulative Perpetual Preferred Stock |  |  |  |  |  |  |
Preferred stock |  |  |  |  |  |  |
Additional members of the board of directors | director |  |  |  |  | 2 |  |
Floating Rate Senior Notes, due 2021 |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |
Debt instrument, face amount |  |  |  | 250,000,000 |  |  |
Floating Rate Senior Notes, due 2023 |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |
Debt instrument, face amount |  |  |  | $ 250,000,000 |  |  |
3.28% Senior Notes, due 2026 |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |
Note stated interest rate (as a percent) |  |  |  |  | 3.28% |  |
4.20% Senior Notes, due 2046 |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |
Note stated interest rate (as a percent) |  |  |  |  | 4.20% |  |
5.10% Subordinated Debentures, due 2053 |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |
Note stated interest rate (as a percent) |  |  |  |  | 5.10% |  |
5.75% Subordinated Debentures, due 2053 |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |
Note stated interest rate (as a percent) |  |  |  |  | 5.75% |  |
Subordinated Debentures |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |
Minimum principal outstanding amount for redemption of debt in whole or in part |  |  |  |  | $ 25,000,000 |  |
Period after occurrence of certain tax and rating agency events in which redemption of debt in whole permissible |  |  |  |  | 90 days |  |
Maximum period for deferment of interest payment |  |  |  |  | 5 years |  |
6.50% Junior Subordinated Debentures, due 2067 |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |
Note stated interest rate (as a percent) |  |  |  |  | 6.50% |  |
Long-term debt |  |  |  |  | $ 500,000,000 |  |
6.125% Junior Subordinated Debentures, due 2067 |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |
Debt instrument, face amount |  |  | $ 224,000,000 |  |  |  |
Note stated interest rate (as a percent) |  |  | 6.125% |  | 6.125% |  |
Debt Instrument, Redemption Price, Percentage of Principal Amount Redeemed |  |  | 100.00% |  |  |  |
6.75% Senior Debentures, due 2018 |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |
Note stated interest rate (as a percent) |  | 6.75% |  |  | 6.75% |  |
Debt Instrument, Redemption Price, Percentage of Principal Amount Redeemed |  | 100.00% |  |  |  |  |
Repayments of Long-term Debt |  | $ 176,000,000 |  |  |  |  |
The Debentures |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |
Maximum period for deferment of interest payment |  |  |  |  | 10 years |  |
Reserved common stock authorized and unissued for debentures obligations (in shares) | shares |  |  |  |  | 75,000,000 |  |
7.45% Senior Notes, due 2019 |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |
Note stated interest rate (as a percent) |  |  |  |  | 7.45% |  |
Threshold percentage of repurchase or redemption of outstanding principal debentures for non applicability of promises and covenants contained in the new RCC |  |  |  |  | 10.00% |  |
Period within which threshold percentage of outstanding principal of debentures is to be purchased for non applicability of promises and covenants contained in the new RCC |  |  |  |  | 1 year |  |
Specified period within which percentage of outstanding principal of debentures is to be purchased for non applicability of promises and covenants contained in the new RCC |  |  |  |  | 10 years |  |
7.45% Senior Notes, due 2019 | Maximum |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |
Percentage of repurchase or redemption of outstanding principal debentures within specified period for non applicability of promises and covenants contained in the new RCC |  |  |  |  | 25.00% |  |
Commercial Paper |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |
Amount of commercial paper outstanding |  |  |  |  | $ 0 | $ 0 |
London Interbank Offered Rate (LIBOR) | Floating Rate Senior Notes, due 2021 |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |
Interest rate spread over LIBOR (as a percent) |  |  |  | 0.43% |  |  |
London Interbank Offered Rate (LIBOR) | Floating Rate Senior Notes, due 2023 |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |
Interest rate spread over LIBOR (as a percent) |  |  |  | 0.63% |  |  |
London Interbank Offered Rate (LIBOR) | 5.10% Subordinated Debentures, due 2053 |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |
Interest rate spread over LIBOR (as a percent) |  |  |  |  | 3.165% |  |
London Interbank Offered Rate (LIBOR) | 5.75% Subordinated Debentures, due 2053 |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |
Interest rate spread over LIBOR (as a percent) |  |  |  |  | 2.938% |  |
London Interbank Offered Rate (LIBOR) | 6.50% Junior Subordinated Debentures, due 2067 |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |
Interest rate spread over LIBOR (as a percent) |  |  |  |  | 2.12% |  |

X
- Definition The amount of additional members of the board of directors to be elected by preferred stock holders if and when dividends have not been declared and paid in full for at least six quarterly dividend periods or their equivalent (whether or not consecutive). + References No definition available. + Details
Name: | all_AdditionalMembersOfBoardOfDirectors
Namespace Prefix: | all_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Represents the collective risk-based capital ratios of subsidiaries expressed as a percentage of net written premiums of insurance business. + References No definition available. + Details
Name: | all_CollectiveRiskBasedCapitalRatiosOfSubsidiariesAsPercentageOfNetWrittenPremiumsOfInsuranceBusiness
Namespace Prefix: | all_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Maximum borrowing capacity under the commercial paper program. + References No definition available. + Details
Name: | all_CommercialPaperMaximumBorrowingCapacity
Namespace Prefix: | all_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- References No definition available. + Details
Name: | all_CommonStockAbstract
Namespace Prefix: | all_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Represents the common shares reserved to satisfy the debt obligations. + References No definition available. + Details
Name: | all_CommonStockAuthorizedAndUnissuedReservedForDebtObligations
Namespace Prefix: | all_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Represents the minimum amount of aggregate outstanding principal amount for initiating redemption of debt in whole or in part on or after maturity date. + References No definition available. + Details
Name: | all_DebtInstrumentMinimumAggregatePrincipalOutstandingAmountForRedemptionOfDebtInWholeOrInPart
Namespace Prefix: | all_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The period after the occurrence of certain tax and rating agency events, which permits the redemption of debt in whole prior to maturity date. + References No definition available. + Details
Name: | all_DebtInstrumentPeriodAfterOccurrenceOfCertainTaxAndRatingAgencyEventsInWhichRedemptionOfDebtInWholePermissible
Namespace Prefix: | all_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Represents the period within which the threshold percentage of outstanding principal of debt is to be purchased for non applicability of promises and covenants contained in the replacement capital covenants. + References No definition available. + Details
Name: | all_DebtInstrumentsReplacementCapitalCovenantsTermsNonApplicabilityPeriodWithinWhichThresholdPercentageOfOutstandingPrincipalDebtIsRepurchasedOrRedeemed
Namespace Prefix: | all_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Represents the percentage of repurchase or redemption of outstanding principal debt for non-applicability of promises and covenants contained in the replacement capital covenants. + References No definition available. + Details
Name: | all_DebtInstrumentsReplacementCapitalCovenantsTermsNonApplicabilitySpecifiedPercentageOfRepurchaseOrRedemptionOfOutstandingPrincipalDebtForSpecifiedPeriod
Namespace Prefix: | all_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Represents the specified period within which the specified percentage of outstanding principal of debt is to be purchased for non applicability of promises and covenants contained in the replacement capital covenants. + References No definition available. + Details
Name: | all_DebtInstrumentsReplacementCapitalCovenantsTermsNonApplicabilitySpecifiedPeriodWithinWhichSpecifiedPercentageOfOutstandingPrincipalDebtIsRepurchasedOrRedeemed
Namespace Prefix: | all_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Represents the threshold percentage of repurchase or redemption of outstanding principal debt for non-applicability of promises and covenants contained in the replacement capital covenants. + References No definition available. + Details
Name: | all_DebtInstrumentsReplacementCapitalCovenantsTermsNonApplicabilityThresholdPercentageOfRepurchaseOrRedemptionOfOutstandingPrincipalDebt
Namespace Prefix: | all_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of additional borrowing allowed under an increase provision contained in the credit facility. + References No definition available. + Details
Name: | all_LineOfCreditFacilityProvisionalIncrementalBorrowing
Namespace Prefix: | all_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The maximum debt to capital resources ratio allowed by the credit facility financial covenant. + References No definition available. + Details
Name: | all_MaximumDebtToCapitalRatioToAvailCreditFacility
Namespace Prefix: | all_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition This element represents the maximum number of years for deferring interest on debt. + References No definition available. + Details
Name: | all_MaximumNumberOfYearsForDeferringInterest
Namespace Prefix: | all_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Represents the percentage by which consolidated shareholders' equity should increase or decrease to avoid restriction on dividends. + References No definition available. + Details
Name: | all_PercentageByWhichConsolidatedShareholdersEquityShouldIncreaseOrDecreaseToAvoidRestrictionOnDividends
Namespace Prefix: | all_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Represent the percentage of decline in consolidated shareholders' equity from benchmark quarter. + References No definition available. + Details
Name: | all_PercentageOfDeclineInConsolidatedShareholdersEquityFromBenchmarkQuarter
Namespace Prefix: | all_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Represents the period before dividend declaration date during which common stock issued can be used to pay preferred stock dividends when restricted due to capital or net income levels. + References No definition available. + Details
Name: | all_PeriodBeforeDividendDeclarationDateConsideredForCommonStockIssueUsedForPreferredDividends
Namespace Prefix: | all_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Represents risk-based capital ratios expressed as a percentage of action level risk-based capital. + References No definition available. + Details
Name: | all_RiskBasedCapitalRatiosAsPercentageOfActionLevelRiskBasedCapital
Namespace Prefix: | all_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition 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. + References No definition available. + Details
Name: | us-gaap_ClassOfStockLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_CommonStockSharesIssued
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_CommonStockSharesOutstanding
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Percentage points added to the reference rate to compute the variable rate on the debt instrument. + References No definition available. + Details
Name: | us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Face (par) amount of debt instrument at time of issuance. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400 + Details
Name: | us-gaap_DebtInstrumentFaceAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Percentage of principal amount of debt redeemed. + References No definition available. + Details
Name: | us-gaap_DebtInstrumentRedemptionPricePercentageOfPrincipalAmountRedeemed
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of cash paid for interest, including, but not limited to, capitalized interest and payment to settle zero-coupon bond attributable to accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount; classified as operating and investing activities. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4297-108586 + Details
Name: | us-gaap_InterestPaid
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Fair value of the amount outstanding under the credit facility. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=109250915&loc=d3e13433-108611 + Details
Name: | us-gaap_LineOfCreditFacilityFairValueOfAmountOutstanding
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6031897-161870 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_LongTermDebt
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of liabilities classified as other. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.15) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
Name: | us-gaap_OtherLiabilities
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The cash outflow to reacquire preferred stock during the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3291-108585 + Details
Name: | us-gaap_PaymentsForRepurchaseOfPreferredStockAndPreferenceStock
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The percentage rate used to calculate dividend payments on preferred stock. + References No definition available. + Details
Name: | us-gaap_PreferredStockDividendRatePercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_PreferredStockIncludingAdditionalPaidInCapitalAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The per share liquidation preference (or restrictions) of nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) that has a preference in involuntary liquidation considerably in excess of the par or stated value of the shares. The liquidation preference is the difference between the preference in liquidation and the par or stated values of the share. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21475-112644 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(d)(1)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(28)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(d)(1)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21484-112644 + Details
Name: | us-gaap_PreferredStockLiquidationPreference
Namespace Prefix: | us-gaap_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Definition Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(28)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_PreferredStockParOrStatedValuePerShare
Namespace Prefix: | us-gaap_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Definition The price per share at which the preferred stock of an entity that has priority over common stock in the distribution of dividends and in the event of liquidation of the entity is redeemed or may be called at. The redemption features of this preferred stock are solely within the control of the issuer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21488-112644 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21475-112644 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21564-112644 + Details
Name: | us-gaap_PreferredStockRedemptionPricePerShare
Namespace Prefix: | us-gaap_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Definition The cash inflow from issuance of preferred stock that is classified as callable. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3255-108585 + Details
Name: | us-gaap_ProceedsFromIssuanceOfRedeemablePreferredStock
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3291-108585 + Details
Name: | us-gaap_RepaymentsOfLongTermDebt
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(19)(a)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)(a)(1)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(13)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
Name: | us-gaap_ShortTermBorrowings
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Number of new stock issued during the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(28)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_StockIssuedDuringPeriodSharesNewIssues
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of shares (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP), net of any shares forfeited. Shares issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(28)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of stock bought back by the entity at the exercise price or redemption price. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644 + Details
Name: | us-gaap_StockRedeemedOrCalledDuringPeriodShares
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Total cost of shares repurchased divided by the total number of shares repurchased. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655 + Details
Name: | us-gaap_TreasuryStockAcquiredAverageCostPerShare
Namespace Prefix: | us-gaap_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.29,30) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655 + Details
Name: | us-gaap_TreasuryStockShares
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of shares that have been repurchased during the period and are being held in treasury. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_TreasuryStockSharesAcquired
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=us-gaap_NoncumulativePreferredStockMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=all_SeriesENoncumulativePreferredStockMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=all_SeriesFNoncumulativePreferredStockMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=all_SeniorNotesDue2021Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=all_SeniorNotesDue2023Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=all_SeniorNotesDue2026at3.28PercentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=all_SeniorNotesDue2046at4.20PercentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=all_SubordinatedDebenturesDue2053At5.10PercentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=all_SubordinatedDebenturesDue2053At5.75PercentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=us-gaap_SubordinatedDebtMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=all_JuniorSubordinatedDebenturesDue2067At6.50PercentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=all_JuniorSubordinatedDebenturesDue2067At6.125PercentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=all_SeniorDebenturesDue2018At6.75PercentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=all_JuniorSubordinatedDebenturesDue2067At6.125PercentAndJuniorSubordinatedDebenturesDue2067At6.50PercentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=all_SeniorNotesDue2019At7.45PercentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ShortTermDebtTypeAxis=us-gaap_CommercialPaperMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_VariableRateAxis=us-gaap_LondonInterbankOfferedRateLIBORMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |