Schedule V - Valuation and Qualifying Accounts and Reserves (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Allowance for Loans and Leases Receivable [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	$ 19	$ 12	$ 17
Charged (Credited) to costs and expenses	10	16	24
Charged (Credited) to other accounts	0	0	0
Other deductions - Describe	(22)	(9)	(29)
Balance at end of period	7	19	12
Allowance for Doubtful Accounts [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	45	49	43
Charged (Credited) to costs and expenses	4	4	11
Charged (Credited) to other accounts	1	(1)	0
Other deductions - Describe	1	(7)	(5)
Balance at end of period	51	45	49
Valuation Allowance of Deferred Tax Assets [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	45	26	117
Charged (Credited) to costs and expenses	4	4	(91)
Charged (Credited) to other accounts	(7)	15	0
Other deductions - Describe	0	0	0
Balance at end of period	42	45	26
Allowance for Reinsurance Recoverable [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	5	10	15
Charged (Credited) to costs and expenses	(1)	(5)	(5)
Charged (Credited) to other accounts	0	0	0
Other deductions - Describe	0	0	0
Balance at end of period	$ 4	$ 5	$ 10