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Loans (Details Textual)	3 Months Ended								12 Months Ended
	Dec. 31, 2019 USD ($)	Sep. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2019 USD ($) Loans	Dec. 31, 2018 USD ($) Loans	Dec. 31, 2017 USD ($)
Financing Receivable Modifications [Line Items]
Total troubled debt restructurings	$ 4,600,000				$ 5,500,000				$ 4,600,000	$ 5,500,000
Specific reserves to customers	61,000				276,000				61,000	276,000
Commitments to lend additional amounts to borrowers classified as troubled debt restructurings	0				0				0	0
Allowance adjustment charge offs									126,000	66,000	$ 75,000
Increase in the allowance for loan losses as a result of the allowance									126,000	66,000	75,000
Provision for loan losses	600,000	$ 550,000	$ 750,000	$ 550,000	525,000	$ 950,000	$ 750,000	$ 775,000	2,450,000	3,000,000	3,350,000
Maximum commercial loan and commercial real estate relationships	750,000								750,000
Residential real estate loan
Financing Receivable Modifications [Line Items]
Total troubled debt restructurings	19,000				146,000				$ 19,000	$ 146,000	$ 0
Troubled debt restructured loans with subsequent payment defaults | Loans | Loans									1	2
Loans default payment past due period									30 days
Provision for loan losses										$ 0
Troubled debt restructurings
Financing Receivable Modifications [Line Items]
Specific reserves to customers	$ 61,000				$ 72,000				$ 61,000	$ 72,000
Contractual Interest Rate Reduction | Minimum
Financing Receivable Modifications [Line Items]
Reduction of the notes stated interest rate									0.24%
Contractual Interest Rate Reduction | Maximum
Financing Receivable Modifications [Line Items]
Reduction of the notes stated interest rate									3.49%
Extended Maturity | Minimum
Financing Receivable Modifications [Line Items]
Maturity period loans									2 months
Extended Maturity | Maximum
Financing Receivable Modifications [Line Items]
Maturity period loans									132 months

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