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Income Taxes (Deferred Tax Assets and Deferred Tax Liabilities) (Details) - USD ($) | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Deferred tax assets: |  |  |
Loans receivable, principally due to the allowance for probable loan losses | $ 12,257,000 | $ 14,546,000 |
Other real estate owned | 2,459,000 | 2,053,000 |
Impairment charges on available-for-sale securities | 1,054,000 | 844,000 |
Accrued expenses | 81,000 | 81,000 |
Net unrealized losses on available for sale investment securities | 15,182,000 | 9,680,000 |
Other | 5,076,000 | 4,434,000 |
Total deferred tax assets | 36,109,000 | 31,638,000 |
Deferred tax liabilities: |  |  |
Bank premises and equipment, principally due to differences on depreciation | (12,596,000) | (10,940,000) |
Identified intangible assets and goodwill | (13,490,000) | (13,417,000) |
Other | (14,787,000) | (12,474,000) |
Total deferred tax liabilities | 40,873,000 | 36,831,000 |
Net deferred tax liability | $ (4,764,000) | $ (5,193,000) |
U.S. Federal income tax rate (as a percent) | 21.00% | 35.00% | 35.00%
Net benefit due to change in tax rate | $ 4,786,000 |  |

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