Basis of Presentation and Significant Accounting Policies Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
	Apr. 29, 1991	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2018	Dec. 31, 2021	Apr. 30, 2013
Finite-Lived Intangible Assets [Line Items]
Operating Lease, Liability		$ 21,543	$ 22,041
Income Taxes Paid		$ 526	$ 381	$ 347
Common Stock Voting Restrictions	10.00%
Common stock, par value (in dollars per share)							$ 0.01
Preferred stock, shares authorized		20,000,000	20,000,000
Preferred Stock, Par or Stated Value Per Share		$ 0.01					$ 0.01
Common stock, shares issued		48,875,167	46,659,144
Common Stock Transfer Restrictions	5.00%
Common Stock Additional Transfer Restrictions					5.00%
Restricted Cash		$ 17,669	$ 11,881	13,612
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents		47,275	19,223	19,940		$ 9,969
Investment income due and accrued		$ 1,703	$ 1,569
Accrued Investment Interest Receivable Write-off Period in Days		90
Financial Assets Allowance for Credit Loss		$ 641
Preferred stock, shares outstanding (in shares)		0	0
Investment income due and accrued		$ 1,703	$ 1,569
CECL Securities Factor for Consideration		20.00%
Specialty Property & Casualty Program
Finite-Lived Intangible Assets [Line Items]
Reinsurance, Reinsured Risk, Percentage		70.00%
Xchange
Finite-Lived Intangible Assets [Line Items]
Ownership percentage		80.00%
All Trans
Finite-Lived Intangible Assets [Line Items]
Ownership percentage		85.00%
Capacity Marine
Finite-Lived Intangible Assets [Line Items]
Ownership percentage		80.00%
Riverton
Finite-Lived Intangible Assets [Line Items]
Ownership percentage		80.00%
Beat
Finite-Lived Intangible Assets [Line Items]
Ownership percentage		60.00%
Minimum [Member] | Furniture and Fixtures [Member]
Finite-Lived Intangible Assets [Line Items]
Useful Life - Years		3 years
Maximum [Member] | Furniture and Fixtures [Member]
Finite-Lived Intangible Assets [Line Items]
Useful Life - Years		5 years
Long-term Debt [Member]
Finite-Lived Intangible Assets [Line Items]
Interest Paid, Including Capitalized Interest, Operating and Investing Activities		$ 3,821	0	0
Variable Interest Entity, Primary Beneficiary [Member]
Finite-Lived Intangible Assets [Line Items]
Restricted Cash		$ 47,275	$ 19,223	$ 19,941