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Income Taxes (Deferred Tax Assets and Deferred Tax Liabilities) (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Deferred tax assets: |  |  |
Loans receivable, principally due to the allowance for probable loan losses | $ 12,050,000 | $ 12,257,000 |
Other real estate owned | 2,501,000 | 2,459,000 |
Impairment charges on available-for-sale securities | 1,054,000 | 1,054,000 |
Accrued expenses | 98,000 | 81,000 |
Net unrealized losses on available for sale investment securities |  | 15,182,000 |
Other | 6,019,000 | 5,076,000 |
Total deferred tax assets | 21,722,000 | 36,109,000 |
Deferred tax liabilities: |  |  |
Bank premises and equipment, principally due to differences on depreciation | (12,478,000) | (12,596,000) |
Net unrealized gains on available for sale investment securities | (508,000) |  |
Identified intangible assets and goodwill | (13,649,000) | (13,490,000) |
Other | (18,849,000) | (14,787,000) |
Total deferred tax liabilities | 45,484,000 | 40,873,000 |
Net deferred tax liability | $ (23,762,000) | $ (4,764,000) |
U.S. Federal income tax rate (as a percent) | 21.00% | 21.00% | 35.00%
Net benefit due to change in tax rate | $ 4,786,000 |  |

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