Goodwill and Other Intangibles (Details Textual) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
Sep. 30, 2010	Dec. 31, 2011 Y	Dec. 31, 2010	Dec. 31, 2009
Goodwill and other intangibles (Textual) [Abstract]
Goodwill		$ 186	$ 186	$ 208
Impairment charges of Goodwill	22
Amortizable intangible assets related to property and casualty insurance acquisitions		41	49
Amortization of intangible assets		12	12	22
Accumulated amortization		47	35
Finite-Lived Intangible Assets, Weighted-Average Useful Life		3
Future amortization of intangibles, Year 2012		14
Future amortization of intangibles, Year 2013		13
Future amortization of intangibles, Year 2014		13
Future amortization of intangibles, after 2014		less than 1 million per year
Non-amortizable intangible assets related to insurance licenses		$ 8

Future amortization of intangibles after year three.

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The accumulated amount of amortization of a major finite-lived intangible asset class. A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

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Aggregate amount of intangible asset amortization recognized as expense during the period.

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The aggregate sum of gross carrying value of a major finite-lived intangible asset class, less accumulated amortization and any impairment charges. A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

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The calculated weighted-average useful life of all finite-lived intangible assets.

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-Name Accounting Standards Codification

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The amount of amortization expense expected to be recognized during year one of the five succeeding fiscal years.

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The amount of amortization expense expected to be recognized during year three of the five succeeding fiscal years.

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The amount of amortization expense expected to be recognized during year two of the five succeeding fiscal years.

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Carrying amount as of the balance sheet date, which is the cumulative amount paid and (if applicable) the fair value of any noncontrolling interest in the acquiree, adjusted for any amortization recognized prior to the adoption of any changes in generally accepted accounting principles (as applicable) and for any impairment charges, in excess of the fair value of net assets acquired in one or more business combination transactions.

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Loss recognized during the period that results from the write-down of goodwill after comparing the implied fair value of reporting unit goodwill with the carrying amount of that goodwill. Goodwill is assessed at least annually for impairment.

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Sum of the carrying amounts (original costs for current and prior period additions adjusted for impairment, if any) as of the balance sheet date of intangible assets, excluding goodwill, having a projected indefinite period of benefit.

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