Securities - Narrative (Details)	12 Months Ended
	Dec. 31, 2016 USD ($) security	Dec. 31, 2015 USD ($)
Schedule of Available-for-sale Securities [Line Items]
Securities pledged to secure public deposits, repurchase agreements and other | $	$ 202,577,000	$ 173,146,000
FHLB letters of credit used as additional collateral amount | $	$ 130,700,000	70,700,000
Federal Home Loan Bank stock requirement, percentage of outstanding borrowings	4.50%
Federal Reserve Bank stock, stock requirement, percentage of outstanding capital	3.00%
Federal Reserve Bank stock, stock requirement, percentage subject to call	3.00%
Federal Reserve Bank Stock | $	$ 3,559,000	3,535,000
Investment in FHLB stock | $	2,665,000	1,777,000
Other-than-temporary impairment losses recognized | $	$ 0	$ 0
Federal agencies and GSEs
Schedule of Available-for-sale Securities [Line Items]
Number of available for sale securities in unrealized loss positions	21
Mortgage-backed securities
Schedule of Available-for-sale Securities [Line Items]
Number of available for sale securities in unrealized loss positions	37
Number of available for sale securities in unrealized loss positions for 12 months or more	3
Collateralized mortgage obligations
Schedule of Available-for-sale Securities [Line Items]
Number of available for sale securities in unrealized loss positions	1
State and municipal
Schedule of Available-for-sale Securities [Line Items]
Number of available for sale securities in unrealized loss positions	64
Corporate
Schedule of Available-for-sale Securities [Line Items]
Number of available for sale securities in unrealized loss positions	4