Investments - Amortized Cost, Fair Value and Unrealized Gains and (Losses) (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Net Investment Income [Line Items]
Amortized Cost	$ 30,360	$ 188,143
Gross unrealized, gains	365	365
Gross unrealized, losses	0	(5,757)
Fair Value	30,725	182,751
Variable Interest Entity, Primary Beneficiary
Net Investment Income [Line Items]
Amortized Cost	174,054
Gross unrealized, gains	661
Gross unrealized, losses	(3,791)
Fair Value	170,924
U.S. Treasuries
Net Investment Income [Line Items]
Amortized Cost	16,437	27,489
Gross unrealized, gains	152	34
Gross unrealized, losses	0	(421)
Fair Value	16,589	27,102
U.S. Treasuries | Variable Interest Entity, Primary Beneficiary
Net Investment Income [Line Items]
Amortized Cost	9,876
Gross unrealized, gains	57
Gross unrealized, losses	(264)
Fair Value	9,669
Obligations of states, municipalities and political subdivisions
Net Investment Income [Line Items]
Amortized Cost	2,075	12,602
Gross unrealized, gains	22	26
Gross unrealized, losses	0	(756)
Fair Value	2,097	11,872
Obligations of states, municipalities and political subdivisions | Variable Interest Entity, Primary Beneficiary
Net Investment Income [Line Items]
Amortized Cost	10,049
Gross unrealized, gains	35
Gross unrealized, losses	(559)
Fair Value	9,525
Corporate bonds
Net Investment Income [Line Items]
Amortized Cost	8,502	72,996
Gross unrealized, gains	137	192
Gross unrealized, losses	0	(2,292)
Fair Value	8,639	70,896
Corporate bonds | Variable Interest Entity, Primary Beneficiary
Net Investment Income [Line Items]
Amortized Cost	79,250
Gross unrealized, gains	339
Gross unrealized, losses	(1,555)
Fair Value	78,034
Residential and commercial mortgage-backed securities
Net Investment Income [Line Items]
Amortized Cost	3,346	62,721
Gross unrealized, gains	54	85
Gross unrealized, losses	0	(2,032)
Fair Value	3,400	60,774
Residential and commercial mortgage-backed securities | Variable Interest Entity, Primary Beneficiary
Net Investment Income [Line Items]
Amortized Cost	62,340
Gross unrealized, gains	184
Gross unrealized, losses	(1,223)
Fair Value	61,301
Other loan-backed and structured securities
Net Investment Income [Line Items]
Amortized Cost	0	12,335
Gross unrealized, gains	0	28
Gross unrealized, losses	0	(256)
Fair Value	0	$ 12,107
Other loan-backed and structured securities | Variable Interest Entity, Primary Beneficiary
Net Investment Income [Line Items]
Amortized Cost	12,539
Gross unrealized, gains	46
Gross unrealized, losses	(190)
Fair Value	$ 12,395