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Commitments and Contingent Liabilities (Details) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2017 | Dec. 31, 2016
Commitments and Contingent Liabilities [Abstract] |  |
Percentage of the Company's loans secured by real estate | 59.00% |
Federal Reserve Bank Requirement [Abstract] |  |
Federal Reserve Bank maintenance period | 14 days |
Average reserve at Federal Reserve Bank for maintenance period | $ 59,000 |
Maximum [Member] |  |
Guarantor Obligations [Line Items] |  |
Obligation instrument term | 5 years |
Unused lines of Credit [Member] |  |
Guarantor Obligations [Line Items] |  |
Commitments - maximum potential obligation | $ 351,227 | $ 292,140
Commitment to Extend Credits, Primarily Variable Rate [Member] |  |
Guarantor Obligations [Line Items] |  |
Commitments - maximum potential obligation | 1,215,187 | 1,177,842
Standby Letters of Credit [Member] |  |
Guarantor Obligations [Line Items] |  |
Commitments - maximum potential obligation | 41,135 | 36,815
Loans Sold with Recourse [Member] |  |
Guarantor Obligations [Line Items] |  |
Commitments - maximum potential obligation | $ 29,120 | $ 28,463

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- Definition For banks and other depository institutions, the calculated average reserve balance outstanding for the specific period as of the Balance Sheet date. Includes noninterest bearing balances with the Federal Reserve Banks. + References No definition available. + Details
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- Definition Describe the approximate period of the guarantee or each group of similar guarantees, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Definition Specific period of time established required to maintain reserve balances with the Federal Reserve Bank, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Definition The percentage of the Company's loans secured by real estate. + References No definition available. + Details
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- Definition Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 460 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=82913245&loc=d3e12069-110248 + Details
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