Summary of Significant Accounting Policies - Summary of Basic and Diluted Income (Loss) per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Numerator:
Net income (loss)	$ 1,324	$ (1,165)
Denominator:
Weighted average common shares outstanding - basic	25,832,190	20,334,929
Basic net income (loss) per share	$ 0.05	$ (0.06)
Numerator:
Net income (loss), basic	$ 1,324	$ (1,165)
Effect of dilutive securities: change in fair value of derivative financial instruments	(2,809)	(434)
Net loss, diluted	$ (1,485)	$ (1,599)
Denominator:
Weighted average common shares outstanding - basic	25,832,190	20,334,929
Potential common share issuances:
Incremental dilutive shares from options and warrants (treasury stock method)	953,518	125,727
Weighted average common shares outstanding - diluted	26,785,708	20,460,656
Diluted net loss per share	$ (0.06)	$ (0.08)