Schedule IV — Reinsurance (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Life insurance in force
Gross amount	$ 21,788,000,000	$ 21,271,000,000	$ 20,535,000,000
Ceded to other companies	482,000,000	614,000,000	640,000,000
Assumed from other companies	1,301,000,000	1,401,000,000	1,528,000,000
Net amount	$ 22,607,000,000	$ 22,058,000,000	$ 21,423,000,000
Percentage of amount assumed to net	5.80%	6.40%	7.10%
Premiums and contract charges:
Gross amount	$ 54,166,000,000	$ 49,390,000,000	$ 45,836,000,000
Ceded to other companies	2,036,000,000	1,906,000,000	1,983,000,000
Assumed from other companies	386,000,000	252,000,000	199,000,000
Net amount	$ 52,516,000,000	$ 47,736,000,000	$ 44,052,000,000
Percentage of amount assumed to net	0.70%	0.50%	0.50%
Reinsurance or coinsurance income netted against premium ceded	$ 0	$ 0	$ 0
Life insurance
Premiums and contract charges:
Gross amount	226,000,000	214,000,000	160,000,000
Ceded to other companies	6,000,000	6,000,000	7,000,000
Assumed from other companies	16,000,000	17,000,000	15,000,000
Net amount	$ 236,000,000	$ 225,000,000	$ 168,000,000
Percentage of amount assumed to net	6.80%	7.60%	8.90%
Accident and health insurance
Premiums and contract charges:
Gross amount	$ 1,639,000,000	$ 1,624,000,000	$ 1,732,000,000
Ceded to other companies	41,000,000	31,000,000	72,000,000
Assumed from other companies	12,000,000	14,000,000	6,000,000
Net amount	$ 1,610,000,000	$ 1,607,000,000	$ 1,666,000,000
Percentage of amount assumed to net	0.70%	0.90%	0.40%
Property and casualty insurance
Premiums and contract charges:
Gross amount	$ 52,301,000,000	$ 47,552,000,000	$ 43,944,000,000
Ceded to other companies	1,989,000,000	1,869,000,000	1,904,000,000
Assumed from other companies	358,000,000	221,000,000	178,000,000
Net amount	$ 50,670,000,000	$ 45,904,000,000	$ 42,218,000,000
Percentage of amount assumed to net	0.70%	0.50%	0.40%