Tax Effects of Temporary Differences That Give Rise to Significant Portions of Net Deferred Tax Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Deferred tax assets:
Discounted unpaid losses and loss adjustment expenses	$ 7,015	$ 8,222
Unearned premiums	8,802	7,884
Section 163(j) carryforward	8,075	3,135
Alternative minimum tax credit carryover	10,957	10,868
Net operating loss carryforward	3,205	1,934
Partnership K1 basis differences	238	245
Capital gain on derivative instruments	4,033	5,340
Investment impairments	3,419	2,635
Stock options	2,820	2,635
Stat-to-GAAP reinsurance reserve	1,337	1,364
Intercompany transfers	808	1,612
Depreciation and amortization		36
Other	4,986	4,545
Total deferred tax assets	55,695	50,455
Deferred tax liabilities:
Purchase accounting adjustment for American Reliable	6,095	6,095
Intangible assets	3,942	3,893
Unrealized gain on securities available-for-sale and investments in limited partnerships included in accumulated other comprehensive income	352	3,896
Investment basis differences	484	1,034
Deferred acquisition costs	2,941	642
Depreciation and amortization	119
Other	805	208
Total deferred tax liabilities	14,738	15,768
Total net deferred tax assets	$ 40,957	$ 34,687