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Loans and ALLL (Narrative) (Details) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2018 USD ($) | Mar. 31, 2018 USD ($) | Mar. 31, 2018 USD ($) | Mar. 31, 2018 USD ($) loan | Mar. 31, 2018 USD ($) NumberofLoan | Mar. 31, 2017 NumberofLoan | Dec. 31, 2017 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |
Threshold period of continuous performance to return loans to accrual status | 6 months |  |  |  |  |  |
Migration analysis of loan portfolio period | 5 years |  |  |  |  |  |
Advance in connection with impaired loans | $ 637 | $ 637 | $ 637 | $ 637 | $ 637 |  | $ 472
Number of loans restructured through the forbearance of principal or accrued interest | NumberofLoan |  |  |  |  | 0 | 0 |
Loans in default |  |  |  | 0 | 0 | 0 |
Minimum [Member] | 4 - Low satisfactory [Member] |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |
Delinquency period | 10 days |  |  |  |  |  |
Minimum [Member] | 5 - Special mention [Member] |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |
Delinquency period | 30 days |  |  |  |  |  |
Maximum [Member] |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |
Financing receivable, amortization term | 30 years |  |  |  |  |  |
Maximum [Member] | 4 - Low satisfactory [Member] |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |
Delinquency period | 30 days |  |  |  |  |  |
Maximum [Member] | 5 - Special mention [Member] |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |
Delinquency period | 60 days |  |  |  |  |  |
Commercial, Agricultural, and Residential Portfolio Segments [Member] |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |
Number of days past due (or more), accrual of interest discontinued | 90 days |  |  |  |  |  |
Total Consumer [Member] |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |
Maximum days of consumer loan charged off | 180 days |  |  |  |  |  |
Total Consumer [Member] | Maximum [Member] |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |
Financing receivable, amortization term | 15 years |  |  |  |  |  |
Commercial And Agricultural Portfolio Segment [Member] |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |
Maximum percentage of loan |  |  | 0.80 |  |  |  |
Commercial And Agricultural Portfolio Segment [Member] | Customer Concentration Risk [Member] |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |
Maximum amount of loans |  | 15,000 |  |  |  |  |
Commercial Advances to Mortgage Brokers Segment [Member] | Customer Concentration Risk [Member] |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |
Maximum amount of loans |  | 30,000 |  |  |  |  |
Commercial Advances to Mortgage Brokers Segment [Member] | Customer Concentration Risk [Member] | Minimum [Member] |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |
Loan advance maturity period | 20 days |  |  |  |  |  |
Commercial Advances to Mortgage Brokers Segment [Member] | Customer Concentration Risk [Member] | Maximum [Member] |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |
Loan advance maturity period | 30 days |  |  |  |  |  |
Residential Real Estate [Member] |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |
Maximum percentage of loan |  |  | 1 |  |  |  |
Maximum percentage of principal, interest, taxes and hazard insurance on property over gross income |  |  | 0.28 |  |  |  |
Maximum percentage of debt servicing over gross income |  |  | 0.40 |  |  |  |
Maximum amount without corporation approval |  | $ 500 |  |  |  |  |
Residential, Privately Insured, Financing Receivable [Member] |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |
Maximum percentage of loan |  |  | 0.80 |  |  |  |

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