Schedule IV - Reinsurance (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Life insurance in force
Gross amount	$ 20,535,000,000	$ 17,124,000,000	$ 18,575,000,000
Ceded to other companies	640,000,000	16,528,000,000	17,801,000,000
Assumed from other companies	1,528,000,000	1,003,000,000	1,062,000,000
Net amount	$ 21,423,000,000	$ 1,599,000,000	$ 1,836,000,000
Percentage of amount assumed to net	7.10%	62.70%	57.80%
Premiums and contract charges:
Property and casualty insurance	$ 45,822,000,000	$ 39,208,000,000	$ 38,249,000,000
Ceded to other companies	1,982,000,000	1,154,000,000	1,136,000,000
Assumed from other companies	199,000,000	113,000,000	108,000,000
Net amount	$ 44,039,000,000	$ 38,167,000,000	$ 37,221,000,000
Percentage of amount assumed to net	0.50%	0.30%	0.30%
Reinsurance or coinsurance income netted against premium ceded	$ 0	$ 0	$ 0
Life insurance
Premiums and contract charges:
Property and casualty insurance	156,000,000	162,000,000	151,000,000
Ceded to other companies	6,000,000	8,000,000	8,000,000
Assumed from other companies	15,000,000	14,000,000	14,000,000
Net amount	$ 165,000,000	$ 168,000,000	$ 157,000,000
Percentage of amount assumed to net	9.10%	8.30%	8.90%
Accident and health insurance
Premiums and contract charges:
Property and casualty insurance	$ 1,722,000,000	$ 931,000,000	$ 994,000,000
Ceded to other companies	72,000,000	5,000,000	6,000,000
Assumed from other companies	6,000,000	0	0
Net amount	$ 1,656,000,000	$ 926,000,000	$ 988,000,000
Percentage of amount assumed to net	0.40%	0.00%	0.00%
Property and casualty insurance
Premiums and contract charges:
Property and casualty insurance	$ 43,944,000,000	$ 38,115,000,000	$ 37,104,000,000
Ceded to other companies	1,904,000,000	1,141,000,000	1,122,000,000
Assumed from other companies	178,000,000	99,000,000	94,000,000
Net amount	$ 42,218,000,000	$ 37,073,000,000	$ 36,076,000,000
Percentage of amount assumed to net	0.40%	0.30%	0.30%