Unpaid Claims - Schedule of Incurred Claims (Details) $ in Thousands	Dec. 31, 2023 USD ($) claim	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Claims Development [Line Items]
Cumulative incurred claims	$ 3,845,797	$ 3,122,689	$ 2,138,604
Total IBNR	$ 137,100
Number of reported claims | claim	13,991,051,000
Unpaid claims	$ 137,100	137,395	136,317
Non-Insurance
Claims Development [Line Items]
Unpaid claims	2,900	6,100
2021 and prior
Claims Development [Line Items]
Cumulative incurred claims	1,938,863	2,099,334	2,138,604
Total IBNR	$ 1,902
Number of reported claims | claim	7,491,528,000
2022
Claims Development [Line Items]
Cumulative incurred claims	$ 910,776	1,023,355	0
Total IBNR	$ 4,652
Number of reported claims | claim	3,358,454,000
2023
Claims Development [Line Items]
Cumulative incurred claims	$ 996,158	$ 0	$ 0
Total IBNR	$ 130,546
Number of reported claims | claim	3,141,069,000