Financing Receivables (Credit Quality Information Text) (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans, gross	$ 3,266	$ 3,263
Commercial mortgage loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans, gross	$ 2,723	$ 2,715
Percentage of commercial mortgage loans with highest risk rating less than %	1.00%	1.00%
Syndicated loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans, gross	$ 543	$ 548
90 days or more past due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonperforming loans	21	16
90 days or more past due | Syndicated loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonperforming loans	$ 8	$ 0