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Securities - Narrative (Details)	3 Months Ended	6 Months Ended
	Jun. 30, 2018 USD ($) Security	Jun. 30, 2018 USD ($) Security	Dec. 31, 2017 USD ($)
Debt Securities, Available-for-sale [Line Items]
Gross gains on sales of securities available for sale | $	$ 12,500	$ 12,500
Carrying value of securities pledged as collateral as required by law on public and trust deposits, repurchase agreements, and for other purposes | $	$ 160,460,000	$ 160,460,000	$ 157,601,000
U.S. Government and agencies
Debt Securities, Available-for-sale [Line Items]
Available for sale securities in unrealized loss positions	68	68
Available for sale securities in unrealized loss positions, percentage of amortized cost (individually did not exceed)	7.00%	7.00%
Available for sale securities in unrealized loss positions for 12 months or more	35	35
Schedule of Held-to-maturity Securities [Line Items]
Held to maturity securities in unrealized loss positions	9	9
Held to maturity securities in unrealized loss positions, percentage of amortized cost (individually did not exceed)	2.00%	2.00%
Held to maturity securities in unrealized loss positions for 12 months or more	7	7
Mortgage-backed securities, residential
Debt Securities, Available-for-sale [Line Items]
Available for sale securities in unrealized loss positions	34	34
Available for sale securities in unrealized loss positions, percentage of amortized cost (individually did not exceed)	5.00%	5.00%
Available for sale securities in unrealized loss positions for 12 months or more	2	2
Schedule of Held-to-maturity Securities [Line Items]
Held to maturity securities in unrealized loss positions	34	34
Held to maturity securities in unrealized loss positions, percentage of amortized cost (individually did not exceed)	5.00%	5.00%
Held to maturity securities in unrealized loss positions for 12 months or more	13	13
State and municipal
Debt Securities, Available-for-sale [Line Items]
Available for sale securities in unrealized loss positions	12	12
Available for sale securities in unrealized loss positions, percentage of amortized cost (individually did not exceed)	9.00%	9.00%
Available for sale securities in unrealized loss positions for 12 months or more	8	8

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