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Nature of Operations and Summary of Significant Accounting Policies (Details Textual) | 3 Months Ended
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Mar. 31, 2018 USD ($) quarter step operating_segment division | Mar. 31, 2017 USD ($)
Number of Bank Divisions | division | 14 |
Number of Operating Segments | operating_segment | 1 |
Minimum Period Past Due to Consider Loan as Delinquent | 30 days |
Minimum Period Past Due to Consider Loan as Non Accrual | 90 days |
Number of Quarters Used to Evaluate Historical Loss Experience | quarter | 12 |
Revenue from Contracts with Customers | $ 17,291,000 | $ 16,270,000
Number of Steps to Achieve Core Revenue Recognition Principal | step | 5 |
Period to begin developing and implementing processes and procedures for FASB Update | 2 years |
Maximum lease term to not recognize lease assets and liabilities | 12 months |
Accounting Standards Update 2017-08 |  |
Effect of cumulative change on retained earnings from applying new accounting pronouncement | $ 22,129,000 |
Consumer and Other |  |
Minimum Number of Days Delinquent to Charge off Loans | 120 days |
Minimum Range |  |
Number of years for home equity loan origination term | 10 years |
Maximum Range |  |
Number of years for home equity loan origination term | 15 years |

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