Net Income (Loss) Per Share Attributable to Common Stockholders (Tables)

3 Months Ended

Mar. 31, 2018

Earnings Per Share [Abstract]

Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]

	Three Months Ended  March 31,
	2018		2017
Net income (loss) attributable to common stockholders – basic calculation	$	1,975	$	(3,506)
Interest charges applicable to convertible promissory notes		295		—
Series B and C preferred dividend		339		—
Series A preferred dividend		(28)		—
Net income (loss) used for net income (loss) per share – diluted calculation		2,581		(3,506)
Shares used to compute net income (loss) per share – basic		3,656,360		135,658
Potential common shares from exercise of options		25,550		—
Shares issuable upon conversion of convertible promissory notes, related party		750,924		—
Shares issuable upon conversion of Series B and C convertible preferred stock and accrued dividends		866,917		—
Shares used to compute net income (loss) per share – diluted		5,299,751		135,658
Net income (loss) per share – basic	$	0.54	$	(25.84)
Net income (loss) per share – diluted	$	0.49	$	(25.84)

Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]

	Three Months Ended March 31,
	2018		2017
Options to purchase common stock		529,332		272,287
Warrant to purchase common stock		5,700		—
Warrant to purchase convertible preferred stock		3,613		7,563
Series B and C convertible preferred stock outstanding, including cumulative dividends		—		1,501,566
Series A convertible preferred stock outstanding		—		94,988
Convertible promissory notes, related party (as converted)		—		687,362
Total potentially dilutive securities excluded from denominator of the diluted earnings per share computation		538,645		2,563,766