Insurance Company Subsidiary Operations - Additional Information (Details) $ in Millions	1 Months Ended	12 Months Ended		13 Months Ended
	Dec. 31, 2021 USD ($)	Dec. 31, 2022 USD ($) Reinsurer	Dec. 31, 2021 USD ($)	Dec. 31, 2022 USD ($)	Sep. 30, 2022
SEC Schedule, 12-17, Insurance Companies, Reinsurance [Line Items]
Ceded rate of premiums under insurance program		100.00%		100.00%
Ceded unpaid loss	$ 63.1	$ 826.2	$ 63.1	$ 826.2
Prepaid reinsurance premiums	392.2	393.2	392.2	393.2
Increase (decrease) in loss and loss adjustment expense reserve		0.0	0.0
Reinsurance recoverable	63.1	831.0	63.1	831.0
Reserve for losses and loss adjustment expense	63.1	$ 826.2	63.1	826.2
Number of reinsurers | Reinsurer		2
Premium net written		$ 38.3
Net earned premiums		26.4
Ultimate loss reserve expense inclusive of IBNR claims	63.1	841.1	63.1	841.1
Hurricane Ian
SEC Schedule, 12-17, Insurance Companies, Reinsurance [Line Items]
Reinsurance recoverable		4.8		4.8
Reinsurance recoverable for net expected loss		4.9		4.9
Loss reserve for non-CAT claims		$ 9.7		$ 9.7
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	392.2	$ 381.8	392.2	$ 381.8
Expenses and allowance rate received in premiums		29.70%		29.70%	29.90%
Premiums written net		$ 740.9	747.4
Statutory capital and surplus required		7.5		$ 7.5
Statutory capital and surplus	33.1	31.8	33.1	$ 31.8
Statutory net Income		$ 1.3	1.6
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 | Federal Flood
SEC Schedule, 12-17, Insurance Companies, Reinsurance [Line Items]
Premiums written net		$ 738.0	$ 745.0
Quota Share Captive
SEC Schedule, 12-17, Insurance Companies, Reinsurance [Line Items]
Prepaid reinsurance premiums		11.4		11.4
Deferred acquisitions costs		14.1		14.1
Reinsurance Payable		8.7		8.7
Reserve for losses and loss adjustment expense		10.4		10.4
Premium net written		38.3
Premiums written net		27.1
Net earned premiums		20.6
Initial funding	$ 5.9
Addition to current earnings				4.0
Ultimate loss reserve expense inclusive of IBNR claims		10.4		10.4
Captive Insurance Facility
SEC Schedule, 12-17, Insurance Companies, Reinsurance [Line Items]
Net earned premiums		5.8
Loss reserve for non-CAT claims		0.1		0.1
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		4.5		4.5
Net earned premiums		2.4
Loss reserve for non-CAT claims		7.0		$ 7.0
Reserve partially offset by accelerated earned premiums		2.8
Underwriting loss		$ 1.9