Summary of Significant Accounting Policies - Summary of Basic and Diluted Loss per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Numerator:
Net loss	$ (1,165)	$ (5,678)
Denominator:
Weighted average common shares outstanding - basic	20,334,929	17,573,966
Basic net loss per share	$ (0.06)	$ (0.32)
Numerator:
Net loss, basic	$ (1,165)	$ (5,678)
Effect of dilutive securities: Change in fair value of derivative financial instruments	(434)
Net loss, diluted	$ (1,599)	$ (5,678)
Weighted average shares outstanding
Weighted average common shares outstanding - basic	20,334,929	17,573,966
Potential common share issuances:
Incremental dilutive shares from stock options and warrants (treasury stock method)	125,727
Weighted average common shares outstanding - diluted	20,460,656	17,573,966
Diluted net loss per share	$ (0.08)	$ (0.32)

Incremental common shares attributable to stock options and warrants.

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Amount of increase (decrease) to net income used for calculating diluted earnings per share (EPS), resulting from the assumed exercise stock options, restrictive stock units (RSUs), convertible preferred stock of an employee stock ownership plan (ESOP), and other dilutive convertible securities.

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (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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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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Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities, and addition from assumption of issuance of common shares for dilutive potential common shares; of income (loss) available to common shareholders.

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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