Fair Value (Carrying Amount And Estimated Fair Value Of Financial Instrument Assets And Liabilities Which Are Not Measured At Fair Value) (Details) (USD $) In Millions	Sep. 30, 2011	Dec. 31, 2010
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Short term debt	$ 1,206	$ 647
Long term debt	8,026	8,830
Financial Assets [Member] \| Carrying Amount [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Other invested assets	204	87
Financial Assets [Member] \| Estimated Fair Value [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Other invested assets	214	86
Financial Liabilities [Member] \| Carrying Amount [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Premium deposits and annuity contracts	108	104
Short term debt	1,206	647
Long term debt	8,026	8,830
Financial Liabilities [Member] \| Estimated Fair Value [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Premium deposits and annuity contracts	110	105
Short term debt	1,210	662
Long term debt	$ 8,633	$ 9,243

Other invested assets, not measured at fair value

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- Definition

Premium deposits and annuity contracts

+ Details

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- Definition

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.

+ Details

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- Definition

Total of the portions of the carrying amounts as of the balance sheet date of long-term debt, which may include notes payable, bonds payable, debentures, mortgage loans, and commercial paper, which are scheduled to be repaid within one year or the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20

-Article 5

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19

-Article 5

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 210.5-02.19,20)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- Definition

Sum of the carrying values as of the balance sheet date of all long-term debt, which is debt initially having maturities due after one year from the balance sheet date or beyond the operating cycle, if longer, but excluding the portions thereof scheduled to be repaid within one year (current maturities) or the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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