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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

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