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Income Taxes - Schedule of Significant Components of Temporary Differences with Deferred Tax Assets and Liabilities (Detail) - USD ($) $ in Thousands | Dec. 31, 2015 | Dec. 31, 2014
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Deferred Tax Liabilities: |  |
Net unrealized holding gains on securities available-for-sale | $ (3,563) | $ (3,783)
Prepaid pension | (2,865) | (3,472)
Deferred loan income | (2,847) | (2,165)
Purchase accounting adjustments | 0 | (631)
Depreciation on premises and equipment | (1,226) | (1,590)
Other | (809) | (812)
Total Deferred Tax liabilities | (11,310) | (12,453)
Deferred Tax Assets: |  |
Allowance for loan losses | 17,740 | 17,567
Purchase accounting adjustments | 1,298 | 0
Other employee benefits | 2,556 | 2,453
Low income housing partnerships | 4,531 | 4,049
Net adjustment to funded status of pension | 12,425 | 11,089
Impairment of securities | 1,354 | 1,313
State net operating loss carryforwards | 2,670 | 2,249
Other | 6,155 | 4,668
Gross Deferred Tax Assets | 48,729 | 43,388
Less: Valuation allowance | (2,670) | (2,249)
Total Deferred Tax Assets | 46,059 | 41,139
Net Deferred Tax Asset | $ 34,749 | $ 28,686

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