Insurance Company Subsidiary Operations - Additional Information (Details) $ in Millions	1 Months Ended	3 Months Ended	12 Months Ended	16 Months Ended
	Dec. 31, 2021 USD ($)	Mar. 31, 2023 USD ($) Reinsurer	Dec. 31, 2022 USD ($)	Mar. 31, 2023 USD ($)
SEC Schedule, 12-17, Insurance Companies, Reinsurance [Line Items]
Ceded rate of premiums under insurance program		100.00%		100.00%
Ceded unpaid loss		$ 139.2		$ 139.2
Prepaid reinsurance premiums		379.6	$ 393.2	379.6
Increase (decrease) in loss and loss adjustment expense reserve		0.0
Reinsurance recoverable		142.7	831.0	142.7
Reserve for losses and loss adjustment expense		$ 139.2		139.2
Number of reinsurers | Reinsurer		2
Premium net written		$ 9.9
Net earned premiums		10.0
Ultimate loss reserve expense inclusive of IBNR claims		154.1	841.1	154.1
Hurricane Ian
SEC Schedule, 12-17, Insurance Companies, Reinsurance [Line Items]
Reinsurance recoverable		3.6		3.6
Reinsurance recoverable for net expected loss		4.2		4.2
Loss reserve for non-CAT claims		7.8		7.8
Reported insured losses		$ 2.4		$ 2.4
Wright National Flood Insurance Company
SEC Schedule, 12-17, Insurance Companies, Reinsurance [Line Items]
Ceded rate of premiums under insurance program		100.00%		100.00%
Prepaid reinsurance premiums		$ 359.6		$ 359.6
Expenses and allowance rate received in premiums		29.70%		29.70%
Premiums written net		$ 162.4
Ceded to highly rated carriers for excess flood policies		0.6
Statutory capital and surplus required		7.5		$ 7.5
Statutory capital and surplus		33.0	31.8	$ 33.0
Statutory net Income		$ 0.5	$ 1.3
Percentage of adjusted net income		100.00%		100.00%
Maximum dividend payout that may be made without prior approval		$ 3.2		$ 3.2
Wright National Flood Insurance Company | Maximum
SEC Schedule, 12-17, Insurance Companies, Reinsurance [Line Items]
Preferred stock, dividend rate, percentage		10.00%
Wright National Flood Insurance Company | FEMA
SEC Schedule, 12-17, Insurance Companies, Reinsurance [Line Items]
Premiums written net		$ 161.8
Quota Share Captive
SEC Schedule, 12-17, Insurance Companies, Reinsurance [Line Items]
Prepaid reinsurance premiums		20.0		20.0
Deferred acquisitions costs		19.4		19.4
Reinsurance payable		5.3		5.3
Reserve for losses and loss adjustment expense		8.6		8.6
Premiums written net		15.9
Premium net written		9.0
Net earned premiums		9.9
Initial funding	$ 5.9
Addition to current earnings				8.5
Ultimate loss reserve expense inclusive of IBNR claims		8.6		8.6
Captive Insurance Facility
SEC Schedule, 12-17, Insurance Companies, Reinsurance [Line Items]
Reserve for losses and loss adjustment expense		6.3		6.3
Net earned premiums		0.9
Maximum underwriting exposure		5.2
Captive Insurance Facility | Hurricane Ian
SEC Schedule, 12-17, Insurance Companies, Reinsurance [Line Items]
Reserve for losses and loss adjustment expense		$ 6.0		$ 6.0