Stock-Based Compensation (Details) $ / shares in Units, $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2018 USD ($) $ / shares shares	Dec. 31, 2017 USD ($) $ / shares shares
Number of Shares
Outstanding - beginning of period \| shares	85,750
Granted \| shares	0
Exercised \| shares	0
Expired \| shares	(8,000)
Forfeited \| shares	(22,875)
Outstanding - end of period \| shares	54,875	85,750
Exercisable - end of period \| shares	54,875
Weighted Average Exercise Price
Outstanding - beginning of period \| $ / shares	$ 5.78
Granted \| $ / shares	0
Exercised \| $ / shares	0
Expired \| $ / shares	6.12
Forfeited \| $ / shares	5.00
Outstanding - end of period \| $ / shares	6.06	$ 5.78
Exercisable - end of period \| $ / shares	$ 6.06
Weighted Average Remaining Contractual Term
Options outstanding	3 years 5 months 8 days	4 years
Options exercisable	3 years 5 months 8 days
Aggregate Intrinsic Value
Outstanding - beginning of period \| $	$ 0
Granted \| $	0
Exercised \| $	0
Expired \| $	0
Forfeited \| $	363
Outstanding - end of period \| $	0	$ 0
Options exercisable \| $	$ 0

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options expired.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options forfeited.

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The aggregate intrinsic value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross number of share options (or share units) granted during the period.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Number of share options (or share units) exercised during the current period.

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