Borrowed Funds - Term Notes from the FHLB (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2018	Dec. 31, 2017
Borrowed funds
Long-term notes from the FHLB	$ 2,513	$ 2,573
Fixed interest rate notes, originating between October 2006 and April 2007, due between October 2021 and April 2022, interest of between 5.18% and 5.20% payable monthly
Borrowed funds
Long-term notes from the FHLB	$ 1,756	1,798
Fixed interest rate notes, originating between October 2006 and April 2007, due between October 2021 and April 2022, interest of between 5.18% and 5.20% payable monthly \| Minimum
Borrowed funds
Interest rate on debt security	5.18%
Fixed interest rate notes, originating between October 2006 and April 2007, due between October 2021 and April 2022, interest of between 5.18% and 5.20% payable monthly \| Maximum
Borrowed funds
Interest rate on debt security	5.20%
Amortizing fixed interest rate note, originating February 2007, due February 2022, payable in monthly installments of $5 thousand, including interest of 5.22%
Borrowed funds
Long-term notes from the FHLB	$ 757	$ 775
Interest rate on debt security	5.22%
Monthly installments	$ 5

Contractual interest rate for funds borrowed, under the debt agreement.

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Including both current and noncurrent portions, Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer.

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