Comprehensive Income and Accumulated Other Comprehensive Income (Loss) - Other Comprehensive Income (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Equity [Abstract]
Unrealized gain on available-for-sale securities, Pre-tax Amount	$ (11,504)	$ 2,555	$ 3,127
Change in unrealized losses on fixed maturity securities with OTTI, Pre-Tax Amount	2	1	(21)
Change in unrealized losses on equity securities with OTTI, Pre-Tax Amount	416
Less amortization of differences between fair value and amortized cost for fixed maturity security transfer, Pre-tax Amount	(75)	(101)	(159)
Less reclassification adjustment for gains realized in net income, Pre-Tax Amount	(30)	(1,279)	107
Change in deferred tax valuation allowance, Pre-Tax Amount
Net unrealized gain, Pre-Tax Amount	(11,191)	1,176	3,054
Other comprehensive income, Pre-Tax Amount	(11,191)	1,176	3,054
Unrealized gain on available-for-sale securities, Tax Expense	(4,027)	894	1,094
Change in unrealized losses on fixed maturity securities with OTTI, Tax Expense	1		(7)
Change in unrealized losses on equity securities with OTTI, Tax Expense	146
Less amortization of differences between fair value and amortized cost for fixed maturity security transfer, Tax Expense	(26)	(35)	(56)
Less reclassification adjustment for gains realized in net income, Tax Expense	(11)	(447)	37
Change in deferred tax valuation allowance, Tax Expense			36
Net unrealized gain, Tax Expense	(3,917)	412	1,104
Other comprehensive income, Tax Expense	(3,917)	412	1,104
Unrealized gain on available-for-sale securities, Net-of-Tax Amount	(7,477)	1,661	2,033
Change in unrealized losses on fixed maturity securities with OTTI, Net-of-Tax Amount	1	1	(14)
Change in unrealized losses on equity securities with OTTI, Net-of-Tax Amount	270
Less amortization of differences between fair value and amortized cost for fixed maturity security transfer, Net-of-Tax Amount	(49)	(66)	(103)
Less reclassification adjustment for gains realized in net income, Net-of-Tax Amount	(19)	(832)	70
Change in deferred tax valuation allowance, Net-of-Tax Amount			(36)
Net unrealized gain, Net-of-Tax Amount	(7,274)	764	1,950
Net current period other comprehensive income	$ (7,274)	$ 764	$ 1,950