Policy Liabilities - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023	Dec. 31, 2022
Liability for Future Policy Benefit, Activity [Line Items]
Change in expected experience, remeasurement gain (loss)	$ 15,600	$ 5,000	$ 23,700	$ (5,600)
Reclassification, Other
Liability for Future Policy Benefit, Activity [Line Items]
Reinsurance recoverables						$ 60,000
Reinsurance recoverable at original discount rates		50,000		50,000
Life
Liability for Future Policy Benefit, Activity [Line Items]
Reinsurance recoverable at original discount rates	43,403	44,195	43,403	44,195
Change in expected experience, remeasurement gain (loss)			17,300	5,100
PV of expected future gross premiums	28,314,644	27,938,263	28,314,644	27,938,263
PV of expected future net premiums	11,981,537	12,042,720	11,981,537	12,042,720	$ 12,164,308	12,342,307	$ 12,189,326	$ 11,748,528
Health
Liability for Future Policy Benefit, Activity [Line Items]
Reinsurance recoverable at original discount rates	14,489	14,842	14,489	14,842
Change in expected experience, remeasurement gain (loss)			6,500	500
PV of expected future gross premiums	11,685,014	10,603,159	11,685,014	10,603,159
PV of expected future net premiums	$ 6,007,794	$ 5,346,643	$ 6,007,794	$ 5,346,643	$ 6,010,536	$ 6,089,728	$ 5,374,493	$ 5,207,422