Reinsurance (Details) (USD $) In Millions	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Reductions to premiums and contract charges due to reinsurance premium ceded amounts
Property-liability insurance premiums earned	$ 274	$ 273	$ 544	$ 541
Life and annuity premiums and contract charges	185	202	378	393
Reductions to costs and expenses due to reinsurance ceded amounts
Property-liability insurance claims and claims expense	61	111	198	191
Life and annuity contract benefits	52	219	136	349
Interest credited to contractholder funds	$ 6	$ 9	$ 14	$ 16

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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Data Type:	xbrli:monetaryItemType
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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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Period Type:	duration

- 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 SEC
-Name Regulation S-X (SX)
-Number 210
-Section 17
-Article 12

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 113
-Paragraph 16

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration