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Earnings per Share - Basic and Diluted (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Numerator:
Net income	$ 236	$ 522	$ 708	$ 1,149
Denominator for basic net income per common share:
Weighted average common shares outstanding (in shares)	12,977,000	12,838,000	12,953,000	12,825,000
Denominator for diluted net income per share:
Dilutive effect of stock options and restricted stock (in shares)	277,000	279,000	275,000	277,000
Diluted weighted average shares (in shares)	13,254,000	13,117,000	13,228,000	13,102,000
Earnings per common share:
Basic (in USD per share)	$ 0.02	$ 0.04	$ 0.05	$ 0.09
Diluted (in USD per share)	$ 0.02	$ 0.04	$ 0.05	$ 0.09
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Number of shares not included in the computation of dilutive income per share (in shares)	126,334	83,917	82,167	83,917
Antidilutive Effect
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Exercise price of shares not included in the computation of dilutive income per share, lower limit (in USD per share)	$ 22.90	$ 28.15	$ 28.15	$ 28.15
Exercise price of shares not included in the computation of dilutive income per share, upper limit (in USD per share)	$ 33.36	$ 33.36	$ 33.36	$ 33.36

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