Financing Receivables (Credit Quality Information Tables) (Details 3) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Commercial mortgage loans
Total loans, gross	$ 3,340	$ 3,263
Less: allowance for loan losses	23	24	$ 26	$ 29
Commercial mortgage loans [Member]
Commercial mortgage loans
Total loans, gross	2,797	2,715
Less: allowance for loan losses	19	19
Total loans, net	$ 2,778	$ 2,696
Percentage of gross commercial mortgage loans	100.00%	100.00%
Commercial mortgage loans [Member] | Apartments [Member]
Commercial mortgage loans
Total loans, gross	$ 692	$ 621
Percentage of gross commercial mortgage loans	25.00%	23.00%
Commercial mortgage loans [Member] | Hotel [Member]
Commercial mortgage loans
Total loans, gross	$ 51	$ 43
Percentage of gross commercial mortgage loans	2.00%	1.00%
Commercial mortgage loans [Member] | Industrial [Member]
Commercial mortgage loans
Total loans, gross	$ 429	$ 453
Percentage of gross commercial mortgage loans	15.00%	17.00%
Commercial mortgage loans [Member] | Mixed Use [Member]
Commercial mortgage loans
Total loans, gross	$ 78	$ 54
Percentage of gross commercial mortgage loans	3.00%	2.00%
Commercial mortgage loans [Member] | Office
Commercial mortgage loans
Total loans, gross	$ 419	$ 435
Percentage of gross commercial mortgage loans	15.00%	16.00%
Commercial mortgage loans [Member] | Retail
Commercial mortgage loans
Total loans, gross	$ 931	$ 897
Percentage of gross commercial mortgage loans	33.00%	33.00%
Commercial mortgage loans [Member] | Other
Commercial mortgage loans
Total loans, gross	$ 197	$ 212
Percentage of gross commercial mortgage loans	7.00%	8.00%
Commercial mortgage loans [Member] | East North Central [Member]
Commercial mortgage loans
Total loans, gross	$ 239	$ 216
Percentage of gross commercial mortgage loans	9.00%	8.00%
Commercial mortgage loans [Member] | East South Central [Member]
Commercial mortgage loans
Total loans, gross	$ 121	$ 107
Percentage of gross commercial mortgage loans	4.00%	4.00%
Commercial mortgage loans [Member] | Middle Atlantic [Member]
Commercial mortgage loans
Total loans, gross	$ 182	$ 187
Percentage of gross commercial mortgage loans	6.00%	7.00%
Commercial mortgage loans [Member] | Mountain [Member]
Commercial mortgage loans
Total loans, gross	$ 251	$ 237
Percentage of gross commercial mortgage loans	9.00%	9.00%
Commercial mortgage loans [Member] | New England [Member]
Commercial mortgage loans
Total loans, gross	$ 54	$ 62
Percentage of gross commercial mortgage loans	2.00%	2.00%
Commercial mortgage loans [Member] | Pacific [Member]
Commercial mortgage loans
Total loans, gross	$ 831	$ 814
Percentage of gross commercial mortgage loans	30.00%	30.00%
Commercial mortgage loans [Member] | South Atlantic [Member]
Commercial mortgage loans
Total loans, gross	$ 723	$ 731
Percentage of gross commercial mortgage loans	26.00%	27.00%
Commercial mortgage loans [Member] | West North Central [Member]
Commercial mortgage loans
Total loans, gross	$ 214	$ 213
Percentage of gross commercial mortgage loans	8.00%	8.00%
Commercial mortgage loans [Member] | West South Central [Member]
Commercial mortgage loans
Total loans, gross	$ 182	$ 148
Percentage of gross commercial mortgage loans	6.00%	5.00%