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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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