Closed Block (Revenues and Expenses) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenues
Premiums	$ 1,580	$ 1,672	$ 1,736
Net investment income	1,740	1,758	1,818
Net investment gains (losses)	(7)	(71)	1
Net derivative gains (losses)	12	22	(32)
Total revenues	3,325	3,381	3,523
Expenses
Policyholder benefits and claims	2,291	2,475	2,453
Policyholder dividends	924	968	976
Other expenses	111	117	125
Total expenses	3,326	3,560	3,554
Revenues, net of expenses before provision for income tax expense (benefit)	(1)	(179)	(31)
Provision for income tax expense (benefit)	(2)	(39)	12
Revenues, net of expenses and provision for income tax expense (benefit)	$ 1	$ (140)	$ (43)