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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 | Dec. 31, 2015
Deferred tax assets: |  |  |  |
Loans receivable, principally due to the allowance for probable loan losses |  | $ 14,546,000 | $ 24,315,000 |
Other real estate owned |  | 2,053,000 | 3,652,000 |
Impairment charges on available-for-sale securities |  | 844,000 | 6,086,000 |
Accrued expenses |  | 81,000 | 137,000 |
Net unrealized losses on available for sale investment securities |  | 9,680,000 | 14,791,000 |
Other |  | 4,434,000 | 6,917,000 |
Total deferred tax assets |  | 31,638,000 | 55,898,000 |
Deferred tax liabilities: |  |  |  |
Bank premises and equipment, principally due to differences on depreciation |  | (10,940,000) | (19,837,000) |
Identified intangible assets and goodwill |  | (13,417,000) | (21,386,000) |
Other |  | (12,474,000) | (16,300,000) |
Total deferred tax liabilities |  | 36,831,000 | 57,523,000 |
Net deferred tax liability |  | (5,193,000) | $ (1,625,000) |
Income tax refund |  | $ 4,900,000 |  |
U.S. Federal income tax rate (as a percent) |  | 35.00% | 35.00% | 35.00%
Net benefit due to change in tax rate |  | $ 3,168,000 |  |
Forecast |  |  |  |
Deferred tax liabilities: |  |  |  |
U.S. Federal income tax rate (as a percent) | 21.00% |  |  |

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- Definition Amount of deferred tax liability attributable to taxable temporary differences. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(15)(b)(2)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(15)(2)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(26)(a)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(26)(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319 + Details
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- Definition Amount of deferred tax liability attributable to taxable temporary differences from intangible assets including goodwill. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32632-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 25 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=96869850&loc=d3e28680-109314 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32621-109319 + Details
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