Below investment grade assets included in fixed income securities.

No definition available.

Name:	all_DebtSecuritiesBelowInvestmentGrade
Namespace Prefix:	all_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

This element represents the fixed income securities that do not produce any income.

+ References

No definition available.

+ Details

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Namespace Prefix:	all_
Data Type:	xbrli:monetaryItemType
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- Details

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Period Type:	duration

- Definition

This element represents the amount of municipal bonds as a percentage of total carrying value.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The minimum percentage of municipal bonds to total carrying value that is used as a threshold for disclosure.

+ References

No definition available.

+ Details

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Namespace Prefix:	all_
Data Type:	num:percentItemType
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Period Type:	instant

- Details

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- Definition

Interest earned on collateral received for loaned securities and invested in short-term investments and fixed income securities, net of fees.

+ References

No definition available.

+ Details

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

- Definition

Threshold percentage which the entity uses for disclosure.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Carrying amount of cash and investment securities on deposit with state regulatory authorities in connection with capital requirements.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 320

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6485772&loc=d3e22002-158495

+ Details

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Balance Type:	debit
Period Type:	instant

- Details

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Balance Type:	na
Period Type:	duration

- Definition

Carrying value of securities loaned to other entities.

+ References

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

-Publisher AICPA

-Name Audit and Accounting Guide (AAG)

-Number AAG-BRD

-Paragraph 32

-IssueDate 2006-05-01

-Chapter 4

-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 Statement of Financial Accounting Standard (FAS)

-Number 140

-Paragraph 91, 93

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 30

-Section 50

-Paragraph 1A

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=7523297&loc=SL6224234-111729

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 140

-Paragraph 17

-Subparagraph a

-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 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 940

-SubTopic 405

-Section 55

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6476329&loc=d3e44140-110984

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Balance Type:	credit
Period Type:	instant

Investments (Details 14) (USD $)	12 Months Ended
Investments (Details 14) (USD $)	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Municipal Bonds
Threshold percentage of municipal to total carrying value	5.00%
Securities loaned
Fixed income and equity securities loaned	$ 760,000,000	$ 406,000,000
Interest Income on collateral, net of fees	2,000,000	2,000,000	2,000,000
Other investment information
Below investment grade assets	6,620,000,000	6,010,000,000
Fixed income securities and short-term investments deposited with regulatory authorities	280,000,000
Non-income producing fixed income securities and other investments	$ 23,000,000
Shareholders' equity \| Concentration of credit risk \| Minimum
Municipal Bonds
Percentage of credit concentration risk of single issuer and affiliates of shareholder's equity	10.00%
Texas
Municipal Bonds
Percentage of municipal bonds carrying value	8.20%	7.70%
California
Municipal Bonds
Percentage of municipal bonds carrying value	8.10%	10.40%
Florida
Municipal Bonds
Percentage of municipal bonds carrying value	6.50%	5.90%
New York
Municipal Bonds
Percentage of municipal bonds carrying value	5.90%	5.30%