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- Definition

Commercial Mortgage Asset Backed Securities In Unrealized Loss Positions Qualitative Disclosure Severity

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- Definition

Commitments to purchase various privately placed debt securities, including bank loans

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- Definition

Commitments to sell various privately placed debt securities including bank loans

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- Definition

Future Capital Call Commitments

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- Definition

The number of different asset-backed structured securities making up the fair value of total asset-backed securities

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- Definition

Number of limited partnership investments held

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- Definition

Other Asset Backed Securities In Unrealized Loss Positions Qualitative Disclosure Severity

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- Definition

Percentage of carrying value reported on a current basis

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Percentage of carrying value reported on one month lag

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- Definition

Percentage of limited partnerships employing hedge fund strategies focused on distressed investments

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- Definition

Percentage Of Limited Partnerships Employing Hedge Fund Strategies Focused On Equity Investments

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- Definition

Percentage of limited partnerships employing hedge fund strategies focused on fixed income investments

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- Definition

Percentage of limited partnerships employing hedge fund strategies with a multi-strategy approach

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- Definition

Percentage Of Limited Partnerships Held That Employ Hedge Fund Strategies

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- Definition

Percentage of limited partnerships invested in private debt and equity

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- Definition

Pretax net unrealized gains on available-for-sale securities reclassified out of AOCI into earnings.

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- Definition

Reduction in net unrealized gains on investments in AOCI supporting certain insurance products, net of tax and noncontrolling interests.

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- Definition

Severity of Unrealized loss as a percentage of amortized cost for Residential Mortgage backed securities

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- Definition

This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

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

-Publisher FASB

-Name FASB Staff Position (FSP)

-Number FAS115-1/124-1

-Paragraph 7

-Footnote 2

-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 Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 19

-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 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.2)

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- Definition

Disclosure regarding factors used to determine that the impairment of securities not categorized as either held-to-maturity securities or trading securities (hence equal to available for sale securities) where cost exceeds fair value is not an other than temporary impairment (OTTI). This item contains disclosure of the number of investment positions in the available-for-sale investments determined to be temporarily impaired.

+ References

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

-Publisher FASB

-Name Emerging Issues Task Force (EITF)

-Number 03-1

-Paragraph 21

-Subparagraph b(3)

-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.

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-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 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 6

-Subparagraph (b)(3)

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- Definition

The fair value as of the balance sheet date of firm holdings in mortgages, mortgage backed securities (investment instruments that represent ownership of an undivided interest in a group of mortgages, where principal and interest from the individual mortgages are used to pay investors' principal and interest on the mortgage backed security) and asset-backed securities that are primarily paid from the cash flows of a discrete pool of receivables or other financial assets (such as credit-card receivables), either fixed or revolving, that by their terms convert into cash within a finite time period. Includes both pledged (to counterparties as collateral for financing transactions) and unpledged holdings.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 940

-SubTopic 320

-Section 45

-Paragraph 2

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents investment securities as of the balance sheet date which may include marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Available-for-Sale Securities

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 13

-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 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Trading Securities

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Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 12

-Subparagraph a

-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 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 7

-Section 03

-Paragraph 1

-Subparagraph a, f, g

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 35

-Paragraph 1

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- Definition

The amount of the limited partners' ownership interests.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 5

-Subparagraph (SAB TOPIC 4.F)

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-Name Accounting Standards Codification

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-SubTopic 10

-Section 50

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 4

-Section F

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Emerging Issues Task Force (EITF)

-Number 87-21

-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 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Practice Bulletin (PB)

-Number 14

-Paragraph 2, 10, 15

-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.

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Investments (Narrative) (Details) (USD $)	3 Months Ended		9 Months Ended		12 Months Ended
Investments (Narrative) (Details) (USD $)	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Dec. 31, 2010
Investment [Line Items]
Pretax net unrealized gains on available-for-sale securities reclassified out of AOCI into earnings	$ (29,000,000)	$ 62,000,000	$ 12,000,000	$ 133,000,000
Severity of unrealized loss as a percentage of amortized cost for residential mortgage-backed securities	7.60%		7.60%
Carrying value of limited partnerships	3,000,000,000		3,000,000,000		2,800,000,000
Percentage of carrying value reported on a current basis			61.80%
Reduction in net unrealized gains on investments in AOCI supporting certain insurance products, net of tax and noncontrolling interests			420,000,000		135,000,000
Percentage of carrying value reported on one month lag			25.00%
Number of limited partnership investments held			86		84
Percentage of limited partnerships held that employ hedge fund strategies	84.70%		84.70%		87.40%
Percentage of limited partnerships employing hedge fund strategies focused on equity investments	43.10%		43.10%
Percentage of limited partnerships employing hedge fund strategies with a multi-strategy approach	36.70%		36.70%
Future capital call commitments	157,000,000		157,000,000
Percentage of limited partnerships employing hedge fund strategies focused on distressed investments	14.90%		14.90%
Percentage of limited partnerships employing hedge fund strategies focused on fixed income investments	5.30%		5.30%
Percentage of limited partnerships invested in private debt and equity	11.00%		11.00%		9.10%
Commitments to purchase various privately placed debt securities including bank loans	110,000,000		110,000,000
Commitments to sell various privately placed debt securities including bank loans	51,000,000		51,000,000
Aggregate Amortized Cost	38,079,000,000		38,079,000,000		37,656,000,000
Asset-Backed Securities [Member]
Investment [Line Items]
Fair value of total asset-backed holdings	8,135,000,000		8,135,000,000
Number of different asset backed securities comprising total fair value of asset backed securities	2,055		2,055
Residential Mortgage-Backed [Member]
Investment [Line Items]
Investment owned, balance, contracts	149		149
Agency Mortgage-Backed Securities [Member]
Investment [Line Items]
Investment owned, balance, contracts	66		66
Commercial Mortgage-Backed [Member]
Investment [Line Items]
Severity of unrealized loss as a percentage of amortized cost for Commercial Mortgage backed securities	8.60%		8.60%
Other Asset-Backed [Member]
Investment [Line Items]
Investment owned, balance, contracts	46		46
Severity of unrealized loss as a percentage of amortized cost for states, municipalities and political subdivision securities	3.10%		3.10%
Sub-Prime/Alt-A Asset Backed Securities [Member]
Investment [Line Items]
Investment owned, balance, contracts	132		132
Corporate And Other Bonds [Member]
Investment [Line Items]
Aggregate fair value	1,702,000,000		1,702,000,000
Aggregate Amortized Cost	$ 1,793,000,000		$ 1,793,000,000