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Income Taxes - Significant Components of Temporary Differences (Details) - USD ($) $ in Thousands | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | ---
Deferred Tax Assets: |  |
Allowance for loan losses | $ 13,798 | $ 13,463
Net unrealized losses on securities available-for-sale | 0 | 1,091
Other employee benefits | 3,039 | 2,712
Low income housing partnerships | 3,494 | 3,249
Net adjustment to funded status of pension | 5,438 | 5,173
Lease liabilities | 11,257 |
State net operating loss carryforwards | 5,134 | 4,573
Other | 1,856 | 2,856
Gross Deferred Tax Assets | 44,016 | 33,117
Less: Valuation allowance | (5,134) | (4,573)
Total Deferred Tax Assets | 38,882 | 28,544
Deferred Tax Liabilities: |  |
Net unrealized gains on securities available-for-sale | (2,570) | 0
Prepaid pension | (5,971) | (6,164)
Deferred loan income | (3,555) | (3,219)
Purchase accounting adjustments | (1,269) | (100)
Depreciation on premises and equipment | (592) | (477)
Right-of-use lease assets | (10,476) |
Other | (1,243) | (1,375)
Total Deferred Tax liabilities | (25,676) | (11,335)
Net Deferred Tax Asset | $ 13,206 | $ 17,209

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