Description of Business and Summary of Significant Accounting Policies - Concentrations (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Five Commercial Banks | Cash and Cash Equivalents
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cash in bank	$ 263.6
Three Commercial Banks | Cash and Cash Equivalents
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cash in bank		$ 148.0
Accounts Receivable | Customer Concentration Risk | Customer One
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Concentration risk, percentage	10.00%	10.00%
Accounts Receivable | Customer Concentration Risk | Customer Two
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Concentration risk, percentage	10.00%	10.00%
Accounts Receivable | Customer Concentration Risk | Customer Three
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Concentration risk, percentage	10.00%
Accounts Receivable | Customer Concentration Risk | Customer Four
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Concentration risk, percentage	10.00%
Accounts Receivable | Customer Concentration Risk | Top Reinsurers
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Concentration risk, percentage	57.00%
Accounts Receivable | Customer Concentration Risk | Two Reinsurers
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Concentration risk, percentage		45.00%
Revenue Benchmark | Geographic Concentration Risk | Customers in Texas
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Concentration risk, percentage	64.00%	52.00%	61.00%
Revenue Benchmark | Geographic Concentration Risk | Customers in South Carolina
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Concentration risk, percentage	11.00%	10.00%	9.00%