Reinsurance (Details) (USD $) In Millions	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Reductions to premiums and contract charges due to reinsurance premium ceded amounts
Property-liability insurance premiums earned	$ 277	$ 270	$ 821	$ 811
Life and annuity premiums and contract charges	180	192	558	585
Reductions to costs and expenses due to reinsurance ceded amounts
Property-liability insurance claims and claims expense	287	11	485	202
Life and annuity contract benefits	207	267	343	616
Interest credited to contractholder funds	$ 7	$ 8	$ 21	$ 24

Premiums and contract charges related to life insurance, accident and health insurance and annuity contracts that are assumed and earned by another insurer as a result of reinsurance arrangements.

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- Definition

The amount in the period for estimated recoupment of interest credited expense under annuity contracts ceded.

+ Details

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- Definition

The amount in the period for estimated recoupment of contract benefits under life insurance, accident and health insurance, and annuity contracts ceded.

+ Details

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- Definition

The amount in the period for estimated recoupment of claims and claims expense under property-liability insurance policies ceded.

+ Details

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- Details

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- Definition

Premiums assumed and earned by another insurer as a result of reinsurance arrangements.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 605

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6486662&loc=d3e27175-158546

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 17

-Article 12

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 113

-Paragraph 16

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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

-Topic 944

-SubTopic 605

-Section 50

-Paragraph 1

-Subparagraph (b),(c)(2)

-URI http://asc.fasb.org/extlink&oid=6486672&loc=d3e27261-158547

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