Fair Value (Details Textual) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value assets liabilities transfers amount between level 1 and level 2	$ 0	$ 0	$ 0	$ 0
Impaired loans, unpaid principal balance with allowance recorded	2,666		2,666		$ 1,636
Impaired loans, allowance	318		318		162
Provision for loan losses	950	950	2,475	2,950
Troubled debt restructurings	5,600		$ 5,600		5,000
Maximum maturity period of short term borrowings			90 days
Measured Using Present Value of Cash Flows
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Troubled debt restructurings	707		$ 707		763
Collateral Dependent Impaired Loans
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Impaired loans, unpaid principal balance with allowance recorded	1,900		1,900		851
Impaired loans, allowance	267		267		$ 109
Provision for loan losses	$ 94	$ 16	$ 222	$ 173