Related Party Transactions (Effects of Affiliated Reinsurance on Statements of Operations) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Premiums:
Net premiums	$ 5,290	$ 6,356	$ 15,259	$ 16,562
Other revenues:
Net other revenues	411	372	1,187	1,176
Interest Credited To Policyholder Account Balances [Abstract]
Net interest credited to policyholder account balances	538	668	1,720	1,993
Other expenses:
Net other expenses	1,360	1,297	3,738	3,680
Affiliated Entity | Assumed Reinsurance [Member]
Premiums:
Reinsurance assumed	2	2	6	7
Universal life and investment-type product policy fees:
Reinsurance assumed	0	0	0	0
Other revenues:
Reinsurance assumed	(3)	(7)	(12)	(16)
Policyholder benefits and claims:
Reinsurance assumed	0	1	1	3
Interest Credited To Policyholder Account Balances [Abstract]
Reinsurance assumed	7	7	21	22
Other expenses:
Reinsurance assumed	0	0	0	0
Affiliated Entity | Ceded Reinsurance [Member]
Premiums:
Reinsurance ceded	(26)	(27)	(84)	(86)
Universal life and investment-type product policy fees:
Reinsurance ceded	(1)	(3)	(3)	(12)
Other revenues:
Reinsurance ceded	143	136	394	402
Policyholder benefits and claims:
Reinsurance ceded	(45)	(60)	(114)	(118)
Interest Credited To Policyholder Account Balances [Abstract]
Reinsurance ceded	(3)	(2)	(9)	(8)
Other expenses:
Reinsurance ceded	128	138	382	402
Affiliated Entity | Reinsurance [Member]
Premiums:
Net premiums	(24)	(25)	(78)	(79)
Universal life and investment-type product policy fees:
Insurance Commissions and Fees, Net Impact from Reinsurance	(1)	(3)	(3)	(12)
Other revenues:
Net other revenues	140	129	382	386
Policyholder benefits and claims:
Net policyholder benefits and claims	(45)	(59)	(113)	(115)
Interest Credited To Policyholder Account Balances [Abstract]
Net interest credited to policyholder account balances	4	5	12	14
Other expenses:
Net other expenses	$ 128	$ 138	$ 382	$ 402