Investments (Details 32) (USD $) In Millions	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Allowance for Loan and Lease Losses, Provision for Loss, Net
Beginning Balance	$ 621	$ 751	$ 664	$ 721
Provision/(release)	(55)	(8)	(94)	33
Charge-offs, net of recoveries	0	(9)	(4)	(20)
Ending Balance	566	734	566	734
Commercial mortgage loans portfolio segment [Member]
Allowance for Loan and Lease Losses, Provision for Loss, Net
Beginning Balance	532	624	562	589
Provision/(release)	(63)	(3)	(93)	32
Charge-offs, net of recoveries	0	0	0	0
Ending Balance	469	621	469	621
Agricultural mortgage loans portfolio segment [Member]
Allowance for Loan and Lease Losses, Provision for Loss, Net
Beginning Balance	76	110	88	115
Provision/(release)	3	(7)	(6)	(1)
Charge-offs, net of recoveries	0	(7)	(3)	(18)
Ending Balance	79	96	79	96
Residential mortgage loans portfolio segment [Member]
Allowance for Loan and Lease Losses, Provision for Loss, Net
Beginning Balance	13	17	14	17
Provision/(release)	5	2	5	2
Charge-offs, net of recoveries	0	(2)	(1)	(2)
Ending Balance	$ 18	$ 17	$ 18	$ 17

Reflects the amount charged against earnings during the period as bad debt expense, net of recoveries of previously expensed credit losses.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 114
-Paragraph 20

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 7
-Subparagraph d
-Article 9

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- Definition

The reserve to cover probable credit losses related to specifically identified fixed maturity real estate loans as well as probable credit losses inherent in the remainder of that 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

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- Definition

Reflects the amount of loans and leases that have been removed, or charged off, from both loan receivables and the reserve for credit losses, typically because they are considered to be not salvageable or have been purchased by unconsolidated collection entities.

+ References

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