Reinsurance (Effects of Reinsurance on Balance Sheet) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Assets
Premiums, reinsurance and other receivables relating to variable interest entities	$ 17,149	$ 17,870
Deferred Policy Acquisition Costs and Present Value of Future Insurance Profits, Net	16,061	16,389	$ 17,833
Total assets	33,210	34,259
Liabilities
Future policy benefits	199,721	206,656
Policyholder account balances	203,473	205,176
Other policy-related balances	17,751	17,101
Other liabilities	22,538	23,614
Total liabilities	443,483	452,547
Direct Reinsurance [Member]
Assets
Premiums, reinsurance and other receivables relating to variable interest entities	4,929	5,032
Deferred Policy Acquisition Costs and Present Value of Future Insurance Profits, Net	16,151	16,482
Total assets	21,080	21,514
Liabilities
Future policy benefits	195,915	203,000
Policyholder account balances	203,391	204,906
Other policy-related balances	16,380	15,769
Other liabilities	15,519	16,283
Total liabilities	431,205	439,958
Assumed Reinsurance [Member]
Assets
Premiums, reinsurance and other receivables relating to variable interest entities	1,789	2,107
Deferred Policy Acquisition Costs and Present Value of Future Insurance Profits, Net	227	230
Total assets	2,016	2,337
Liabilities
Future policy benefits	3,806	3,656
Policyholder account balances	82	270
Other policy-related balances	1,368	1,332
Other liabilities	2,139	2,417
Total liabilities	7,395	7,675
Ceded Reinsurance [Member]
Assets
Premiums, reinsurance and other receivables relating to variable interest entities	10,431	10,731
Deferred Policy Acquisition Costs and Present Value of Future Insurance Profits, Net	(317)	(323)
Total assets	10,114	10,408
Liabilities
Future policy benefits	0	0
Policyholder account balances	0	0
Other policy-related balances	3	0
Other liabilities	4,880	4,914
Total liabilities	$ 4,883	$ 4,914