Warrants to Purchase Common Stock (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	12 Months Ended
	Jun. 30, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 06, 2016
Class of Warrant or Right [Line Items]
Warrant expense included in research and development expenses			$ 400
Reduction of expense warrant		$ 100
Savant Warrant [Member]
Class of Warrant or Right [Line Items]
Issuance of warrant to purchase shares of common stock	200,000
Exercise price of warrants issued (in dollars per share)	$ 2.25
Warrants initial fair value	$ 700
Term of issuance of warrant	5 years
Percentage of warrant exercisable	25.00%
Warrant [Member]
Class of Warrant or Right [Line Items]
Issuance of warrant to purchase shares of common stock				25,000
Exercise price of warrants issued (in dollars per share)				$ 4.00
Warrants initial fair value				$ 40