Consolidated Statements of Stockholders' Equity (Deficit) - USD ($) $ in Thousands	Total	Series A-1 Convertible Preferred Stock [Member]	Eiccose LLC [Member]	Convertible Preferred Stock [Member]	Convertible Preferred Stock [Member] Series A-1 Convertible Preferred Stock [Member]	Common Stock [Member]	Common Stock [Member] Eiccose LLC [Member]	Additional Paid-In Capital [Member]	Additional Paid-In Capital [Member] Eiccose LLC [Member]	Accumulated Other Comprehensive Loss [Member]	Accumulated Deficit [Member]
Beginning Balance at Dec. 31, 2013	$ 105							$ 1,087			$ (14,433)
Temporary equity, Beginning balance at Dec. 31, 2013				$ 13,451
Beginning Balance, Shares at Dec. 31, 2013						193,850
Temporary equity, Beginning balance, Shares at Dec. 31, 2013				1,228,418
Issuance of stock		$ 1,915			$ 1,915
Issuance of stock, Shares					290,856
Stock-based compensation expense	27							27
Net loss	(1,516)										(1,516)
Ending Balance at Dec. 31, 2014	531							1,114			(15,949)
Temporary equity, Ending balance at Dec. 31, 2014				$ 15,366
Ending Balance, Shares at Dec. 31, 2014						193,850
Temporary equity, Ending balance, Shares at Dec. 31, 2014				1,519,274
Issuance of stock		$ 7,201			$ 7,201
Issuance of stock, Shares					1,089,828
Issuance of common stock in connection with a license and asset purchase agreement	211							211
Issuance of common stock in connection with a license and asset purchase agreement, Shares						15,378
Issuance of common stock upon stock option exercises, Shares						64,765
Stock-based compensation expense	227							227
Net loss	(13,322)										(13,322)
Ending Balance at Dec. 31, 2015	$ (5,152)							1,552			(29,271)
Temporary equity, Ending balance at Dec. 31, 2015				$ 22,567
Ending Balance, Shares at Dec. 31, 2015	273,993					273,993
Temporary equity, Ending balance, Shares at Dec. 31, 2015				2,609,102
Issuance of common stock upon private placement, net of $1,300 of issuance cost	$ 32,108					$ 2		32,106
Issuance of common stock upon private placement, net of $1,300 of issuance cost, Shares						1,954,390
Conversion of preferred stock into common stock, Temporary equity value	6,129			$ (22,567)				6,129
Issuance of common stock upon conversion of convertible promissory note, Shares						350,040
Conversion of preferred stock into common stock, Temporary equity shares				(2,609,102)
Issuance of common stock upon exercise of warrants	1,057							1,057
Issuance of common stock upon exercise of warrants, Shares						61,254
Issuance of common stock to Eiccose upon private placement			$ 1,661						$ 1,661
Issuance of common stock to Eiccose upon private placement, Shares							96,300
Conversion of preferred stock into common stock						$ 3		22,564
Conversion of preferred stock into common stock, Shares						2,609,102
Issuance of common stock upon reverse merger	27,390					$ 2		27,388
Issuance of common stock upon reverse merger, Shares						1,596,959
Issuance of stock	18,229					$ 1		18,228
Issuance of stock, Shares						1,250,000
Issuance of common stock in connection with a license and asset purchase agreement	3,172							3,172
Issuance of common stock in connection with a license and asset purchase agreement, Shares						157,587
Issuance of common stock upon stock option exercises	$ 39							39
Issuance of common stock upon stock option exercises, Shares	7,034					7,034
Stock-based compensation expense	$ 3,190							3,190
Unrealized loss on marketable securities, net	(15)									$ (15)
Net loss	(47,087)										(47,087)
Ending Balance at Dec. 31, 2016	$ 40,721					$ 8		$ 117,086		$ (15)	$ (76,358)
Ending Balance, Shares at Dec. 31, 2016	8,356,659					8,356,659