Consolidated Supplementary Insurance Information (Income Statement Items) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information [Line Items]
Premiums and Universal Life and Investment-Type Product Policy Fees	$ 3,829	$ 4,059	$ 3,984
Net Investment Income	3,486	3,235	2,973
Policyholder Benefits and Claims and Interest Credited to Policyholder Account Balances	4,569	4,227	4,670
Amortization of DAC and VOBA	395	1,011	916
Other Expenses	1,809	1,763	1,833
Annuities
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information [Line Items]
Premiums and Universal Life and Investment-Type Product Policy Fees	2,291	2,410	2,448
Net Investment Income	1,786	1,509	1,238
Policyholder Benefits and Claims and Interest Credited to Policyholder Account Balances	1,429	1,603	2,140
Amortization of DAC and VOBA	328	901	141
Other Expenses	1,125	1,052	1,035
Life
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information [Line Items]
Premiums and Universal Life and Investment-Type Product Policy Fees	728	774	713
Net Investment Income	374	371	285
Policyholder Benefits and Claims and Interest Credited to Policyholder Account Balances	646	637	681
Amortization of DAC and VOBA	53	93	186
Other Expenses	177	214	237
Run-off
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information [Line Items]
Premiums and Universal Life and Investment-Type Product Policy Fees	720	777	715
Net Investment Income	1,273	1,311	1,358
Policyholder Benefits and Claims and Interest Credited to Policyholder Account Balances	2,436	1,923	1,788
Amortization of DAC and VOBA	0	0	570
Other Expenses	200	202	278
Corporate & Other
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information [Line Items]
Premiums and Universal Life and Investment-Type Product Policy Fees	90	98	108
Net Investment Income	53	44	92
Policyholder Benefits and Claims and Interest Credited to Policyholder Account Balances	58	64	61
Amortization of DAC and VOBA	14	17	19
Other Expenses	$ 307	$ 295	$ 283