Statutory Financial Information - Additional Information (Detail) - Wright Flood - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Statutory Accounting Practices [Line Items]
Statutory capital and surplus required	$ 7,500,000
Statutory capital and surplus	15,100,000	$ 10,900,000
Statutory net Income	$ 4,100,000	$ 2,300,000