Financing Receivables (Details 2) (USD $)	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Commercial mortgage loans
Loans and Leases Receivable, Impaired, Commitment to Lend	$ 0
Percent of commercial mortgage loans with highest risk rating	2.00%
Total loans	3,941,000,000	4,012,000,000
Less: allowance for loan losses	37,000,000	44,000,000	60,000,000	64,000,000
Commercial Mortgage Loans
Commercial mortgage loans
Percent of commercial mortgage loans with highest risk rating	2.00%	2.00%
Total loans	2,682,000,000	2,606,000,000
Less: allowance for loan losses	26,000,000	29,000,000
Net commercial mortgage loans	2,656,000,000	2,577,000,000
Percentage of gross commercial mortgage loans	100.00%	100.00%
Commercial Mortgage Loans | Apartments
Commercial mortgage loans
Total loans	488,000,000	450,000,000
Percentage of gross commercial mortgage loans	18.00%	17.00%
Commercial Mortgage Loans | Hotel
Commercial mortgage loans
Total loans	33,000,000	36,000,000
Percentage of gross commercial mortgage loans	1.00%	1.00%
Commercial Mortgage Loans | Industrial
Commercial mortgage loans
Total loans	454,000,000	474,000,000
Percentage of gross commercial mortgage loans	17.00%	18.00%
Commercial Mortgage Loans | Mixed Use
Commercial mortgage loans
Total loans	36,000,000	42,000,000
Percentage of gross commercial mortgage loans	1.00%	2.00%
Commercial Mortgage Loans | Office
Commercial mortgage loans
Total loans	559,000,000	610,000,000
Percentage of gross commercial mortgage loans	21.00%	24.00%
Commercial Mortgage Loans | Retail
Commercial mortgage loans
Total loans	951,000,000	858,000,000
Percentage of gross commercial mortgage loans	36.00%	33.00%
Commercial Mortgage Loans | Other
Commercial mortgage loans
Total loans	161,000,000	136,000,000
Percentage of gross commercial mortgage loans	6.00%	5.00%
Commercial Mortgage Loans | East North Central
Commercial mortgage loans
Total loans	251,000,000	260,000,000
Percentage of gross commercial mortgage loans	9.00%	10.00%
Commercial Mortgage Loans | East South Central
Commercial mortgage loans
Total loans	71,000,000	66,000,000
Percentage of gross commercial mortgage loans	3.00%	3.00%
Commercial Mortgage Loans | Middle Atlantic
Commercial mortgage loans
Total loans	211,000,000	207,000,000
Percentage of gross commercial mortgage loans	8.00%	8.00%
Commercial Mortgage Loans | Mountain
Commercial mortgage loans
Total loans	257,000,000	272,000,000
Percentage of gross commercial mortgage loans	10.00%	10.00%
Commercial Mortgage Loans | New England
Commercial mortgage loans
Total loans	149,000,000	146,000,000
Percentage of gross commercial mortgage loans	5.00%	6.00%
Commercial Mortgage Loans | Pacific
Commercial mortgage loans
Total loans	661,000,000	597,000,000
Percentage of gross commercial mortgage loans	25.00%	23.00%
Commercial Mortgage Loans | South Atlantic
Commercial mortgage loans
Total loans	713,000,000	661,000,000
Percentage of gross commercial mortgage loans	26.00%	25.00%
Commercial Mortgage Loans | West North Central
Commercial mortgage loans
Total loans	207,000,000	232,000,000
Percentage of gross commercial mortgage loans	8.00%	9.00%
Commercial Mortgage Loans | West South Central
Commercial mortgage loans
Total loans	$ 162,000,000	$ 165,000,000
Percentage of gross commercial mortgage loans	6.00%	6.00%