Deferred Policy Acquisition Costs (Details 1) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Summary of amortization of deferred policy acquisition costs
Amortization of deferred policy acquisition costs	$ 151	$ 140	$ 447	$ 435
Property and Casualty Insurance [Member]
Summary of amortization of deferred policy acquisition costs
Amortization of policy acquisition costs	111	102	323	310
Annuity and Supplemental Insurance [Member]
Summary of amortization of deferred policy acquisition costs
Amortization of policy acquisition costs	27	27	86	89
Amortization of deferred policyholder sales inducements	8	6	24	20
Amortization of present value of future profits	5	5	14	16
Amortization of deferred policy acquisition costs	$ 40	$ 38	$ 124	$ 125