Investments (Details 40) (USD $) In Millions	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Fixed maturity securities [Member]
Accretable yield on purchased distressed assets acquired
Accretable yield, beginning of period	$ 708	$ 70	$ 541	$ 0
Investments Purchased	1,089	317	1,221	388
Accretion	(32)	(6)	(49)	(7)
Disposals	(18)	0	(69)	0
Reclassification to/ from nonaccretable difference	144	(12)	247	(12)
Accretable yield, end of period	1,891	369	1,891	369
Mortgage loans, net [Member]
Accretable yield on purchased distressed assets acquired
Accretable yield, beginning of period	176	0	170	0
Investments Purchased	0	0	0	0
Accretion	(20)	0	(32)	0
Reclassification to/ from nonaccretable difference	102	0	120	0
Accretable yield, end of period	$ 258	$ 0	$ 258	$ 0

Relates to investments purchased (fixed maturity securities and loans) with a credit impairment inherent in the estimated fair value.

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- Definition

The aggregate excess of a loan's cash flows expected to be collected over the investor's initial investment in the loan for loans accounted for as debt securities, with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Statement of Position (SOP)
-Number 03-3
-Paragraph 16
-Subparagraph a(2)

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- Definition

Current period recognition due to accretion of the excess of a loan's cash flows expected to be collected over the investor's initial investment in the loan for loans accounted for as debt securities, with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Statement of Position (SOP)
-Number 03-3
-Paragraph 16
-Subparagraph a(2)

+ Details

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- Definition

Sale or transfer of a loan accounted for as a debt security, with evidence of deterioration of credit quality since origination that was acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable, during the period resulting in a reduction in the excess of a loan's cash flows expected to be collected over the investor's initial investment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Statement of Position (SOP)
-Number 03-3
-Paragraph 16
-Subparagraph a(2)

+ Details

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- Definition

Change in the estimate of cash flows expected to be collected, after acquisition of a loan accounted for as a debt security, with evidence of deterioration of credit quality since origination that was acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable, which results in an increase in accreditable yield (for example, if actual cash flows are significantly greater than previously expected).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Statement of Position (SOP)
-Number 03-3
-Paragraph 16
-Subparagraph a(2)

+ Details

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- Definition

The aggregate excess of a loan's cash flows expected to be collected over the investor's initial investment in the loan for loans not accounted for as debt securities, with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Statement of Position (SOP)
-Number 03-3
-Paragraph 16
-Subparagraph a(2)

+ Details

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- Definition

Current period recognition due to accretion of the excess of a loan's cash flows expected to be collected over the investor's initial investment in the loan for loans not accounted for as debt securities, with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Statement of Position (SOP)
-Number 03-3
-Paragraph 16
-Subparagraph a(2)

+ 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.

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- Definition

Change in the estimate of cash flows expected to be collected, after acquisition of loans not accounted for as debt securities, with evidence of deterioration of credit quality since origination that was acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable, which results in an increase in accreditable yield (for example, if actual cash flows are significantly greater than previously expected).

+ References

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-Publisher AICPA
-Name Statement of Position (SOP)
-Number 03-3
-Paragraph 16
-Subparagraph a(2)

+ Details

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