Losses and Loss Adjustment Reserve - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2016 USD ($) Reinsurer	Dec. 31, 2015 USD ($)
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Ceded rate of premiums under insurance program	100.00%
Premiums written net	$ 118,781,000
Ceded unpaid loss	58,100,000
The reinsurance recoverable	337,900,000
Prepaid reinsurance premiums	279,784,000	$ 309,643,000
Increase (Decrease) in Loss and Loss Adjustment Expense Reserve	0
Reserve for losses and loss adjustment expense	$ 58,100,000
Number of reinsurers | Reinsurer	3
Homeowners
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Ceded unpaid loss	$ 8,698
Reinsurance recoverable, incurred but not reported claims	10,335
Private Passenger Auto Liability
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Ceded unpaid loss	24,916
Reinsurance recoverable, incurred but not reported claims	14,383
Other Liability
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Ceded unpaid loss	$ 2,009
Wright Flood
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Ceded rate of premiums under insurance program	100.00%
Expenses and allowance rate received in premiums	30.90%
Premiums written net	$ 118,400,000
Wright Flood | Quota Share Agreement
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Effective cedes rate under quota share agreement	100.00%
Commission rate, percent of ceded written premiums	30.50%
Ceded amount	$ 300,000