CONSOLIDATED STATEMENTS OF OPERATIONS (Parenthetical) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
CONSOLIDATED STATEMENTS OF OPERATIONS
Property-liability insurance premiums, reinsurance ceded	$ 1,090	$ 1,098	$ 1,092
Life and annuity premiums and contract charges, reinsurance ceded	674	750	804
Property-liability insurance claims and claims expense, reinsurance ceded	2,051	927	271
Life and annuity contract benefits, reinsurance ceded	665	653	702
Interest credited to contractholder funds, reinsurance ceded	$ 28	$ 27	$ 32