Stock-Based Compensation (Details) - 2008 LTIP - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Stock-based compensation
Shares authorized to be granted under stock compensation plan	2,000,000
Shares available for future awards	1,312,015
Stock Options
Number Outstanding
Outstanding at beginning of year (in shares)	540,625	90,625
Granted during the year (in shares)		450,000
Forfeited or expired during the year (in shares)	(3,125)
Outstanding at end of year (in shares)	537,500	540,625
Exercisable at end of year (in shares)	177,500	90,625
Weighted Average Exercise Price
Outstanding at beginning of year (in dollars per share)	$ 2.18	$ 4.95
Exercise price of options granted (in dollars per share)		1.62
Forfeited or expired during the year (in dollars per share)	4.80
Outstanding at end of year (in dollars per share)	2.19	2.18
Exercisable at end of year (in dollars per share)	$ 3.26	$ 4.95
Additional disclosures
Stock based compensation expense	$ 39	$ 32
Unrecognized compensation cost	$ 123
Period for recognizing unrecognized compensation cost	3 years 1 month 24 days
Stock Options \| Senior Executive Officers
Stock-based compensation
Vesting period of stock award		5 years
Contractual term of option awards		10 years
Fair value of stock options		$ 194
Stock option per shares (in dollars per share)		$ 0.43
Volatility		27.36%
Risk free interest rate		1.21%
Expected option term		5 years
Dividend yield		0.00%
Number Outstanding
Granted during the year (in shares)	0	450,000
Weighted Average Exercise Price
Exercise price of options granted (in dollars per share)		$ 1.62

Represents the information pertaining to shares available for the future awards.

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- Definition

Fair value of options granted. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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- Definition

The amount of expense, net of income tax, recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Unrecognized cost of unvested options awarded to employees as compensation.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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The risk-free interest rate assumption that is used in valuing an option on its own shares.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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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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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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For presentations that combine terminations, 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 or that expired.

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Weighted average price of options that were either forfeited or expired.

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

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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