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Acquisitions and FDIC Indemnification Asset (Details Textual) - USD ($) | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2016 | Sep. 30, 2017 | Sep. 30, 2016 | Dec. 31, 2016 | Dec. 31, 2015
Business Acquisition [Line Items] |  |  |  |  |
Gain on Sale of certain assets and liabilities of Insurance Brokerage Operation | $ (199,000) | $ 0 | $ 12,822,000 |  |
Assets |  | 2,982,342,000 |  | $ 2,988,527,000 |
Goodwill |  | 34,355,000 |  | 34,355,000 |
Loans and Leases Receivable, Net of Loans with Deteriorated Credit Quality, Covered |  | 4,400,000 |  | 5,100,000 |
First National Bank Of Danville [Member] |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Reimbursements from the FDIC |  | 19,400,000 |  |  |
Business Aquisition, Loss Sharing Agreement Losses On Assets Threshold |  | $ 29,000,000 |  |  |
Business Acquisition Loss Sharing Agreement Losses In Excess Of Threshold To Be Reimbursed Percentage |  | 95.00% |  |  |
Business Acquisition, Loss Sharing Agreement Losses Up To Threshold To Be Reimbursed Percentage |  | 80.00% |  |  |
Forrest Sherer Insurance [Domain] |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Assets |  |  |  | 13,000,000 | $ 15,800,000
Insurance Services Revenue |  |  |  | 7,600,000 | 8,300,000
Operating Income (Loss) |  |  |  | $ 168,000 | $ 554,000

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- Definition Represents the percentage of losses on assets acquired under business combination and covered under loss-sharing agreement, to be reimbursed by FDIC, if losses exceed the threshold amount. + References No definition available. + Details
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- Definition Represents the percentage of losses on assets acquired under business combination and covered under loss-sharing agreement, to be reimbursed by FDIC, if losses are up to the threshold amount. + References No definition available. + Details
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- Definition Gain on Sale of certain Assets and Liabilities of Insurance Brokerage Operation + References No definition available. + Details
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- Definition Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + 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(a)(12)) -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(11)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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- Definition Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.1) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 + Details
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