Income Taxes - Components of Deferred Tax Assets and Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Deferred tax assets:
Unearned premiums	$ 17,979	$ 15,567
Tax-related discount on loss reserve	1,140	1,022
Unrealized loss	1,277
Stock-based compensation	1,617	1,258
Other	257	545
Total deferred tax assets	22,269	18,392
Deferred tax liabilities:
Deferred acquisition costs	13,424	9,401
Unrealized gain		1,081
Property and equipment	473	633
Other	408	655
Total deferred tax liabilities	14,305	11,770
Net deferred tax assets	$ 7,964	$ 6,622