Reinsurance (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Property-liability insurance claims and claims expense
Reductions to costs and expenses due to reinsurance ceded amounts
Ceded losses incurred	$ 120	$ 224	$ 218	$ 442
Life and annuity contract benefits
Reductions to costs and expenses due to reinsurance ceded amounts
Ceded losses incurred	79	83	205	171
Interest credited to contractholder funds
Reductions to costs and expenses due to reinsurance ceded amounts
Ceded losses incurred	9	8	15	14
Property-liability insurance premiums earned
Reductions to premiums and contract charges due to reinsurance premium ceded amounts
Ceded premium earned	262	274	520	547
Life and annuity premiums and contract charges
Reductions to premiums and contract charges due to reinsurance premium ceded amounts
Premiums and contract charges	$ 84	$ 164	$ 237	$ 322