Fair Value of Assets and Liabilities (Details 3) (USD $) In Millions	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Fair Value Liabilities Measured on Recurring Basis Unobservable Input Reconciliation Calculation
Balance at beginning of period	$ (630)	$ (90)	$ (653)	$ (110)
Total realized and unrealized gains (losses) included in net income, recurring Level 3 liabilities	(34)	(30)	(26)	(12)
Issuances	(13)		(27)
Settlements	48		77
Purchases, sales, issuances and settlements, net		1		3
Balance at end of period	(629)	(119)	(629)	(119)
Derivatives embedded in life and annuity contracts
Fair Value Liabilities Measured on Recurring Basis Unobservable Input Reconciliation Calculation
Balance at beginning of period	(630)	(90)	(653)	(110)
Total realized and unrealized gains (losses) included in net income, recurring Level 3 liabilities	(34)	(30)	(26)	(12)
Issuances	(13)		(27)
Settlements	48		77
Purchases, sales, issuances and settlements, net		1		3
Balance at end of period	$ (629)	$ (119)	$ (629)	$ (119)

This element represents a liability measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances.

Name:	all_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilities
Namespace Prefix:	all
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Issues that have taken place during the period in relation to liabilities measured at fair value and categorized within Level 3 of the fair value hierarchy.

+ Details

Name:	all_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityIssues
Namespace Prefix:	all
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Settlements that have taken place during the period in relation to liabilities measured at fair value and categorized within Level 3 of the fair value hierarchy.

+ Details

Name:	all_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements
Namespace Prefix:	all
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

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

+ Details

Name:	us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward
Namespace Prefix:	us-gaap
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

This element represents total gains or losses for the period (realized and unrealized), arising from liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in earnings or resulted in a change in net asset value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 157
-Paragraph 32
-Subparagraph c(1)

+ Details

Name:	us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

This element represents purchases, sales, issuances, and settlements (net) which have taken place during the period in relation to liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 157
-Paragraph 32
-Subparagraph c(2)

+ Details

Name:	us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityPurchasesSalesIssuancesSettlements
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration