Closed Block (Closed Block Revenues and Benefits and Expenses) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Revenues
Premiums	$ 1,981	$ 2,207	$ 2,301
Net investment income	2,255	2,332	2,298
Realized investment gains (losses), net	182	521	130
Other income (loss)	362	589	(39)
Total Closed Block revenues	4,780	5,649	4,690
Benefits and Expenses
Policyholders’ benefits	2,758	2,906	2,972
Interest credited to policyholders’ account balances	127	130	132
Dividends to policyholders	1,549	2,187	1,236
General and administrative expenses	327	351	364
Total Closed Block benefits and expenses	4,761	5,574	4,704
Closed Block revenues, net of Closed Block benefits and expenses, before income taxes	19	75	(14)
Income tax expense (benefit)	(43)	10	(78)
Closed Block revenues, net of Closed Block benefits and expenses and income taxes	$ 62	$ 65	$ 64