Stock-Based Compensation (Details) $ / shares in Units, $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2019 USD ($) $ / shares shares	Dec. 31, 2018 USD ($) $ / shares shares
Number of Shares
Outstanding - beginning of period \| shares	39,000
Granted \| shares	0
Exercised \| shares	(1,000)
Expired \| shares	(18,000)
Forfeited \| shares	(4,000)
Outstanding - end of period \| shares	16,000	39,000
Exercisable - end of period \| shares	16,000
Weighted Average Exercise Price per Share
Outstanding - beginning of period \| $ / shares	$ 6.26
Granted \| $ / shares	0
Exercised \| $ / shares	4.22
Expired \| $ / shares	8.19
Forfeited \| $ / shares	4.22
Outstanding - end of period \| $ / shares	4.73	$ 6.26
Exercisable - end of period \| $ / shares	$ 4.73
Weighted Average Remaining Contractual Term
Options outstanding	4 years 2 months 12 days	2 years 9 months 18 days
Options exercisable	4 years 2 months 12 days
Aggregate Intrinsic Value
Outstanding - beginning of period \| $	$ 4,480
Granted \| $	0
Exercised \| $	950
Expired \| $	0
Forfeited \| $	3,360
Outstanding - end of period \| $	4,903	$ 4,480
Options exercisable \| $	$ 4,903

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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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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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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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

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