Consolidated Reinsurance (Consolidated Reinsurance) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
SEC Schedule, 12-17, Insurance Companies, Reinsurance [Line Items]
Direct Premiums, Life Insurance in Force	$ 5,222,988	$ 5,100,675	$ 4,963,820
Ceded Premiums, Life Insurance in Force	442,381	488,958	507,589
Assumed Premiums, Life Insurance in Force	597,903	623,662	532,511
Premiums, Net, Life Insurance in Force	$ 5,378,510	$ 5,235,379	$ 4,988,742
Life Insurance in Force Premiums, Percentage Assumed to Net	11.10%	11.90%	10.70%
Consolidated Reinsurance
Gross Amount	$ 42,201	$ 42,513	$ 44,199
Ceded	2,199	2,298	2,380
Assumed	2,032	2,020	2,021
Premiums	$ 42,034	$ 42,235	$ 43,840
% Amount Assumed to Net	4.80%	4.80%	4.60%
Life insurance (1)
Consolidated Reinsurance
Gross Amount	$ 23,629	$ 23,938	$ 26,356
Ceded	1,620	1,704	1,792
Assumed	1,809	1,794	1,791
Premiums	$ 23,818	$ 24,028	$ 26,355
% Amount Assumed to Net	7.60%	7.50%	6.80%
Accident & health insurance
Consolidated Reinsurance
Gross Amount	$ 14,958	$ 14,835	$ 14,166
Ceded	516	523	515
Assumed	208	207	212
Premiums	$ 14,650	$ 14,519	$ 13,863
% Amount Assumed to Net	1.40%	1.40%	1.50%
Property and casualty insurance
Consolidated Reinsurance
Gross Amount	$ 3,614	$ 3,740	$ 3,677
Ceded	63	71	73
Assumed	15	19	18
Premiums	$ 3,566	$ 3,688	$ 3,622
% Amount Assumed to Net	0.40%	0.50%	0.50%