Federal Home Loan Bank (FHLB) Advances and Other Short-Term Borrowings (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Other short-term borrowings:
Securities sold under repurchase agreements, Weighted Average Interest Rate	1.38%	0.59%	0.37%
Long-term Debt
Fixed-rate payable and convertible fixed-rate FHLB advances, with monthly interest payments:
Due in 2017		$ 15,500
Due in 2018	$ 4,000	2,000
Due in 2019	6,000
Due in 2020	4,000
Total FHLB advances - long-term	$ 14,000	17,500
Weighted Average Interest Rate Due in 2017	1.22%
Weighted Average Interest Rate Due in 2018	1.60%
Weighted Average Interest Rate Due in 2020	1.70%
Weighted Average Interest Rate, Total FHLB advances - long term	1.51%
Short-term Debt
FHLB advances - short-term:
Short-term	$ 12,000	6,000
Cash management	20,000	17,000
Total FHLB advances - short-term	$ 32,000	23,000
Weighted Average Interest Rate Short term	1.29%
Weighted Average Interest Rate Cash management	1.44%
Total FHLB advances - short term, Weighted Average Interest Rate	1.38%
Total FHLB advances, Weighted Average Interest Rate	1.42%
Total FHLB advances	$ 46,000	40,500
Other short-term borrowings:
Securities sold under repurchase agreements	2,678	2,702
Total FHLB advances and other short-term borrowings	$ 48,678	$ 43,202
Securities sold under repurchase agreements, Weighted Average Interest Rate	0.34%
Total FHLB advances and other short-term borrowings, Weighted Average Interest Rate	1.36%