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Income Taxes (Deferred Tax Assets and Deferred Tax Liabilities) (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Deferred tax assets: |  |  |
Loans receivable, principally due to the allowance for probable loan losses | $ 21,921 | $ 12,050 |
Other real estate owned | 1,183 | 2,501 |
Impairment charges on available-for-sale securities |  | 1,054 |
Accrued expenses | 81 | 98 |
Other | 5,649 | 6,019 |
Total deferred tax assets | 28,834 | 21,722 |
Deferred tax liabilities: |  |  |
Bank premises and equipment, principally due to differences on depreciation | (12,350) | (12,478) |
Net unrealized gains on available for sale investment securities | (5,679) | (508) |
Impairment charges on available-for-securities | (19) |  |
Identified intangible assets and goodwill | (13,807) | (13,649) |
Other | (20,551) | (18,849) |
Total deferred tax liabilities | 52,406 | 45,484 |
Net deferred tax liability | $ (23,572) | $ (23,762) |
U.S. Federal income tax rate (as a percent) | 21.00% | 21.00% | 21.00%

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