Policy Liabilities - Additional Information (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024	Mar. 31, 2024	Dec. 31, 2023
Life
Liability for Future Policy Benefit, Activity [Line Items]
PV of expected future gross premiums, At current discount rates	$ 29,020,613		$ 28,545,056
PV of expected future net premiums	11,942,125	$ 11,757,317	12,164,308	$ 12,342,307
Liability for future policy benefit, difference between expected gross premiums and expected future net premiums	17,100,000		16,300,000
Health
Liability for Future Policy Benefit, Activity [Line Items]
PV of expected future gross premiums, At current discount rates	12,335,780		11,682,884
PV of expected future net premiums	6,469,631	$ 6,314,148	6,010,536	$ 6,089,728
Liability for future policy benefit, difference between expected gross premiums and expected future net premiums	$ 5,800,000		$ 5,700,000