The balance represents the amount of loans that are secured by real estate mortgages.

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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

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 Accounting Standards Codification

-Topic 944

-SubTopic 310

-Section 45

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6873192&loc=d3e21338-158488

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- Definition

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-URI http://asc.fasb.org/extlink&oid=6965416&loc=SL6953423-111524

-Subparagraph (g)

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- Definition

The valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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The balance of financing receivables that were collectively evaluated for impairment.

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The balance of financing receivables that were individually evaluated for impairment.

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- Definition

Reflects the aggregate carrying amount of all categories of loans and leases held in portfolio, net of unearned income and the allowance for losses on loans and leases.

+ References

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

-Publisher AICPA

-Name Statement of Position (SOP)

-Number 01-6

-Paragraph 13

-Subparagraph e

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6375948&loc=d3e4428-111522

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.7)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Investments (Details 31) (USD $) In Millions	Sep. 30, 2011	Jun. 30, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Dec. 31, 2009
Mortgage Loans on Real Estate [Line Items]
Evaluated individually for credit losses	$ 368		$ 279
Evaluated collectively for credit losses	56,143		52,521
Total mortgage loans	56,511		52,800
Specific credit losses	117		88
Non-specifically identified credit losses	412		576
Valuation allowances	529	566	664	666	734	721
Mortgage loan, net of valuation allowance	55,982		52,136
Commercial mortgage loans portfolio segment [Member]
Mortgage Loans on Real Estate [Line Items]
Evaluated individually for credit losses	211		120
Evaluated collectively for credit losses	39,909		37,698
Total mortgage loans	40,120		37,818
Specific credit losses	70		36
Non-specifically identified credit losses	358		526
Valuation allowances	428	469	562	573	621	589
Mortgage loan, net of valuation allowance	39,692		37,256
Agricultural mortgage loans portfolio segment [Member]
Mortgage Loans on Real Estate [Line Items]
Evaluated individually for credit losses	150		146
Evaluated collectively for credit losses	12,817		12,605
Total mortgage loans	12,967		12,751
Specific credit losses	46		52
Non-specifically identified credit losses	36		36
Valuation allowances	82	79	88	76	96	115
Mortgage loan, net of valuation allowance	12,885		12,663
Residential mortgage loans portfolio segment [Member]
Mortgage Loans on Real Estate [Line Items]
Evaluated individually for credit losses	7		13
Evaluated collectively for credit losses	3,417		2,218
Total mortgage loans	3,424		2,231
Specific credit losses	1		0
Non-specifically identified credit losses	18		14
Valuation allowances	19	18	14	17	17	17
Mortgage loan, net of valuation allowance	$ 3,405		$ 2,217