Reinsurance (Effects of Affiliated Reinsurance on Statements of Operations) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Premiums:
Reinsurance assumed	$ 15	$ 12	$ 13
Reinsurance ceded	(765)	(783)	(916)
Net premiums	847	869	828
Universal life and investment-type product policy fees [Abstract]
Reinsurance assumed	79	101	103
Reinsurance ceded	(529)	(528)	(600)
Insurance Commissions and Fees	2,982	3,190	3,156
Other revenues:
Reinsurance assumed	3	2	29
Reinsurance ceded	19	23	47
Net other revenues	266	287	336
Policyholder benefits and claims:
Reinsurance assumed	70	75	89
Reinsurance ceded	(1,799)	(1,619)	(1,575)
Other Expenses [Abstract]
Assumed Other Expenses	(10)	(4)	19
Ceded Other Expenses	(20)	(45)	(21)
Operating Expenses	1,809	1,763	1,833
Affiliated Entity
Universal life and investment-type product policy fees [Abstract]
Insurance Commissions and Fees	220	234	241
Affiliated Entity | Assumed
Premiums:
Reinsurance assumed	5	7	13
Universal life and investment-type product policy fees [Abstract]
Reinsurance assumed	6	51	103
Other revenues:
Reinsurance assumed	3	2	29
Policyholder benefits and claims:
Reinsurance assumed	34	52	87
Other Expenses [Abstract]
Assumed Other Expenses	(32)	(13)	18
Affiliated Entity | Ceded
Premiums:
Reinsurance ceded	0	(201)	(537)
Universal life and investment-type product policy fees [Abstract]
Reinsurance ceded	0	1	(14)
Other revenues:
Reinsurance ceded	0	18	44
Policyholder benefits and claims:
Reinsurance ceded	0	(178)	(420)
Other Expenses [Abstract]
Ceded Other Expenses	0	(5)	0
Affiliated Entity | Reinsurance
Premiums:
Net premiums	5	(194)	(524)
Universal life and investment-type product policy fees [Abstract]
Insurance Commissions and Fees	6	52	89
Other revenues:
Net other revenues	3	20	73
Policyholder benefits and claims:
Policyholder Benefits and Claims Incurred, Assumed and Ceded	34	(126)	(333)
Other Expenses [Abstract]
Operating Expenses	$ (32)	$ (18)	$ 18