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Income Taxes - Significant Components of Temporary Differences (Details) - USD ($) $ in Thousands | Dec. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Deferred Tax Assets: |  |
Allowance for credit losses | $ 22,083 | $ 26,051
Lease liabilities | 10,876 | 11,368
State net operating loss carryforwards | 5,565 | 5,489
Net adjustment to funded status of pension | 3,922 | 4,692
Low income housing partnerships | 3,270 | 3,996
Other employee benefits | 3,433 | 2,050
Other | 3,973 | 3,798
Gross Deferred Tax Assets | 53,122 | 57,444
Less: Valuation allowance | (5,565) | (5,489)
Total Deferred Tax Assets | 47,557 | 51,955
Deferred Tax Liabilities: |  |
Right-of-use lease assets | (9,603) | (10,141)
Net unrealized gains on securities available-for-sale | (2,004) | (7,125)
Deferred loan income | (6,697) | (6,796)
Prepaid pension | (4,566) | (5,209)
Purchase accounting adjustments | (1,954) | (1,971)
Depreciation on premises and equipment | (1,107) | (1,275)
Other | (1,466) | (1,245)
Total Deferred Tax liabilities | (27,397) | (33,762)
Net Deferred Tax Asset | $ 20,160 | $ 18,193

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