Net Loss Per Share - Computation of Basic and Diluted Loss Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Numerator:
Net loss	$ (598)	$ (1,285)
Less: preferred stock dividends	15	3
Net loss attributable to common stockholders	$ (613)	$ (1,288)
Denominator:
Weighted-average number of shares of common stock for basic and diluted net loss per share (in shares)	5,104	4,623
Basic and diluted net loss per share (in dollars per share)	$ (0.12)	$ (0.28)

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The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders.

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The amount of preferred stock dividends that is an adjustment to net income apportioned to common stockholders.

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Average number of shares or units issued and outstanding that are used in calculating basic and diluted earnings per share (EPS).

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