Investments (Details 12) (USD $) In Millions	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2011	Dec. 31, 2010
Carrying value of non-impaired mortgage loans, summarized by debt service coverage ratio distribution
Total mortgage loans	$ 6,827	$ 6,827	$ 6,679
Mortgage loans, non-impaired
Carrying value of non-impaired mortgage loans, summarized by debt service coverage ratio distribution
Fixed rate mortgage loans	6,361	6,361	5,923
Variable rate mortgage loans	292	292	567
Total mortgage loans	6,653	6,653	6,490
Net carrying value of impaired mortgage loans
Impaired mortgage loans with a valuation allowance	153	153	168
Impaired loans without a valuation allowance	21	21	21
Total impaired mortgage loans	174	174	189
Valuation allowance on impaired mortgage loans	68	68
Average carrying value and interest income recognized on impaired mortgage loans
Average impaired mortgage loans		178
Rollforward of the valuation allowance on impaired mortgage loans
Valuation allowance on impaired mortgage loans, beginning balance	77	84
Net increase in valuation allowance	7	13
Charge offs	(16)	(29)
Valuation allowance on impaired mortgage loans, ending balance	68	68
Carrying value of past due mortgage loans
Less than 90 days past due	27	27	12
90 days or greater past due	48	48	78
Total past due	75	75	90
Current loans	6,752	6,752	6,589
Mortgage loans, non-impaired \| Below 1.0
Carrying value of non-impaired mortgage loans, summarized by debt service coverage ratio distribution
Fixed rate mortgage loans	327	327	280
Total mortgage loans	327	327	280
Mortgage loans, non-impaired \| 1.0 - 1.25
Carrying value of non-impaired mortgage loans, summarized by debt service coverage ratio distribution
Fixed rate mortgage loans	1,622	1,622	1,583
Variable rate mortgage loans			16
Total mortgage loans	1,622	1,622	1,599
Mortgage loans, non-impaired \| 1.26 - 1.50
Carrying value of non-impaired mortgage loans, summarized by debt service coverage ratio distribution
Fixed rate mortgage loans	1,672	1,672	1,520
Variable rate mortgage loans	26	26	5
Total mortgage loans	1,698	1,698	1,525
Mortgage loans, non-impaired \| Above 1.50
Carrying value of non-impaired mortgage loans, summarized by debt service coverage ratio distribution
Fixed rate mortgage loans	2,740	2,740	2,540
Variable rate mortgage loans	266	266	546
Total mortgage loans	$ 3,006	$ 3,006	$ 3,086

A valuation allowance for financing receivables that are expected to be uncollectible.

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- Definition

Charge to expense for financing receivables that are expected to be uncollectible.

+ Details

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- Definition

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

+ Details

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- Definition

Reduction to the allowance for credit losses related to financing receivables deemed uncollectible.

+ Details

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- Details

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- Details

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Namespace Prefix:	all
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- Definition

Financing receivables that are current.

+ Details

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- Definition

Financing receivables that are equal to or greater than 90 days past due.

+ Details

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- Definition

Financing receivables that are less than 90 days past due.

+ Details

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- Definition

Recorded Investment in financing receivables that are past due at the balance sheet date.

+ Details

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- Details

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- Definition

The average recorded investment related to impaired financing receivables.

+ Details

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- Definition

The recorded investment related to impaired financing receivables.

+ Details

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Namespace Prefix:	all
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- Definition

The recorded investment related to impaired financing receivables without a specific valuation allowance.

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- Definition

The recorded investment related to impaired financing receivables with a specific valuation allowance.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Reflects the carrying amount of loans charging borrowers fixed rates of interest.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Reflects the carrying amount of loans charging borrowers variable, or adjustable, rates of interest.

+ Details

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Balance Type:	credit
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- Definition

The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 60
-Paragraph 47

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 1
-Subparagraph c
-Article 7

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