Supplemental Cash Flow Information (Details) (USD $) In Millions	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010
Supplemental Cash Flow Information
Non-cash investment exchanges, including modifications of certain mortgage loans (primarily refinances at maturity with no concessions granted to the borrower), fixed income securities, limited partnerships and other investments, as well as mergers completed with equity securities	$ 513	$ 353
Net change in proceeds managed
Net change in short-term investments	(421)	211
Operating cash flow (used) provided	(421)	211
Net change in cash	(2)	2
Net change in proceeds managed	(423)	213
Net change in liabilities
Liabilities for collateral, beginning of year	(484)	(658)
Liabilities for collateral, end of period	(907)	(445)
Operating cash flow provided (used)	$ 423	$ (213)

The net operating cash flow provided by (used in) the net change in liabilities for collateral.

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- Definition

The net operating cash flow provided or used related to collateral received in conjunction with the entity's securities lending and over-the-counter derivatives.

+ Details

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- Definition

The net change in cash from the proceeds managed related to collateral received in conjunction with the entity's securities lending and over-the-counter derivatives.

+ Details

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- Details

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- Details

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- Definition

The net change in the proceeds managed related to collateral received in conjunction with the entity's securities lending and over-the-counter derivatives.

+ Details

Name:	all_NetChangeInProceedsManagedCollateral
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- Definition

The 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.

+ Details

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- Definition

The liability to return cash and securities received as collateral in conjunction with securities lending and over-the-counter derivatives.

+ Details

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- Details

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- Definition

Value of investments transferred in noncash transactions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 32

+ Details

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