Basis of Presentation and Summary of Significant Accounting Policies - Goodwill and Intangible Assets (Details) - USD ($)	3 Months Ended
	Mar. 31, 2025	Dec. 31, 2024
Business Acquisition
Goodwill	$ 46,062,000	$ 46,062,000
Indefinite-lived intangibles	7,500,000	7,500,000
Total goodwill and intangibles	53,562,000	53,562,000
Goodwill and intangible asset impairment	0
Surety
Business Acquisition
Goodwill	40,816,000	40,816,000
Casualty
Business Acquisition
Goodwill	$ 5,246,000	$ 5,246,000