Segment Information - Schedule of Segment Results (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Segment Reporting Information [Line Items]
Gross written premiums	$ 1,172,319	$ 1,431,772	$ 1,508,660
Net earned premiums	600,288	600,196	708,005
Fee income	2,416	4,585	5,301
Total incurred losses and loss and adjustment expenses	427,204	554,374	500,157
Less: losses and loss adjustment expense - retroactive reinsurance	28,750	37,237	4,991
Losses and loss adjustment expenses excluding retroactive reinsurance	398,454	517,137	495,166
Other operating expenses:
Net commissions	48,450	44,943	48,733
Employee compensation	94,036	100,095	98,430
All other operating expenses	41,478	48,160	46,493
Total	183,964	193,198	193,656
Underwriting loss (profit)	20,286	(105,554)	24,484
Segment revenues	687,614	707,626	812,009
Net investment income	83,440	93,089	84,046
Interest expense	23,538	24,666	24,627
Segment goodwill	181,831	181,831	181,831
Segment assets	4,859,930	5,007,076
Segment assets			4,533,857
Excess and Surplus Lines | Operating Segments
Segment Reporting Information [Line Items]
Gross written premiums	963,035	1,017,029	1,007,351
Net earned premiums	559,490	512,237	609,566
Fee income	0	0	0
Total incurred losses and loss and adjustment expenses	386,824	485,951	425,035
Less: losses and loss adjustment expense - retroactive reinsurance	28,750	37,237	4,991
Losses and loss adjustment expenses excluding retroactive reinsurance	358,074	448,714	420,044
Other operating expenses:
Net commissions	59,633	56,186	61,542
Employee compensation	61,257	62,176	57,436
All other operating expenses	21,054	22,616	16,197
Total	141,944	140,978	135,175
Underwriting loss (profit)	59,472	(77,455)	54,347
Segment revenues	625,505	594,433	690,388
Net investment income	65,291	73,341	69,325
Interest expense	0	0	0
Segment goodwill	181,831	181,831	181,831
Segment assets	3,652,130	3,516,399
Segment assets			3,083,798
Specialty Admitted Insurance
Segment Reporting Information [Line Items]
Gross written premiums	174,800
Fee income	2,400	4,600	5,300
Specialty Admitted Insurance | Operating Segments
Segment Reporting Information [Line Items]
Gross written premiums	209,284	414,743	501,309
Net earned premiums	40,798	87,959	98,439
Fee income	2,416	4,585	5,301
Total incurred losses and loss and adjustment expenses	40,380	68,423	75,122
Less: losses and loss adjustment expense - retroactive reinsurance	0	0	0
Losses and loss adjustment expenses excluding retroactive reinsurance	40,380	68,423	75,122
Other operating expenses:
Net commissions	(11,183)	(11,243)	(12,809)
Employee compensation	9,774	14,115	18,492
All other operating expenses	9,936	14,376	18,858
Total	8,527	17,248	24,541
Underwriting loss (profit)	(5,693)	6,873	4,077
Segment revenues	60,286	109,472	119,777
Net investment income	17,011	16,937	13,568
Interest expense	0	0	0
Segment goodwill	0	0	0
Segment assets	1,134,689	1,390,894
Segment assets			1,387,020
Corporate and Other | Segment Reporting, Reconciling Item, Corporate Nonsegment
Segment Reporting Information [Line Items]
Gross written premiums	0	0	0
Net earned premiums	0	0	0
Fee income	0	0	0
Total incurred losses and loss and adjustment expenses	0	0	0
Less: losses and loss adjustment expense - retroactive reinsurance	0	0	0
Losses and loss adjustment expenses excluding retroactive reinsurance	0	0	0
Other operating expenses:
Net commissions	0	0	0
Employee compensation	23,005	23,804	22,502
All other operating expenses	10,488	11,168	11,438
Total	33,493	34,972	33,940
Underwriting loss (profit)	(33,493)	(34,972)	(33,940)
Segment revenues	1,823	3,721	1,844
Net investment income	1,138	2,811	1,153
Interest expense	23,538	24,666	24,627
Segment goodwill	0	0	0
Segment assets	$ 73,111	$ 99,783
Segment assets			$ 63,039