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Income Taxes (Net Deferred Tax Assets) (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Income Tax Disclosure [Abstract] |  |
Allowance for credit losses | $ 14,239 | $ 7,810
Leases - right of use obligations | 5,510 | 5,474
Deferred compensation | 1,149 | 1,095
Investment in limited partnerships | 1,418 | 1,191
SERP agreements | 323 | 418
Interest on nonaccrual loans | 88 | 191
Share-based compensation | 602 | 586
Other | 148 | 224
Gross deferred tax assets | 23,477 | 16,989
Leases - right of use assets | 5,113 | 5,474
Prepaid expenses | 635 | 498
Prepaid pension costs | 1,183 | 897
Intangible assets | 2,286 | 2,643
Depreciation and amortization | 2,046 | 1,961
Net unrealized gain on securities available for sale | 5,079 | 301
Loan servicing assets | 338 | 289
Other | 627 | 550
Gross deferred tax liabilities | 17,307 | 12,613
Net deferred tax asset | $ 6,170 | $ 4,376

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