Subsequent Events - Narrative (Details) $ / shares in Units, $ in Thousands	Oct. 24, 2017 USD ($) $ / shares shares	Sep. 30, 2017 $ / shares shares	Dec. 31, 2016 $ / shares shares
Subsequent Event [Line Items]
Registered direct offering, convertible, shares issued (in shares) | shares		32	32
Stated value (in dollars per share) | $ / shares		$ 0.0001	$ 0.0001
Series B-1 Preferred Stock
Subsequent Event [Line Items]
Registered direct offering, convertible, shares issued (in shares) | shares		0
Subsequent Event | Series B-1 Preferred Stock
Subsequent Event [Line Items]
Registered direct offering, convertible, shares issued (in shares) | shares	2,800
Gross proceeds from issuance of stock | $	$ 2,800
Estimated net proceeds from issuance of stock | $	$ 2,325
Stated value (in dollars per share) | $ / shares	$ 1,000
Conversion of preferred stock (in dollars per share) | $ / shares	$ 0.28
Right of participation for future offerings, maximum percentage (up to)	100.00%
Right of participation for future offerings, period of time following closing date	24 months
Expansion of board of director members, period of time following closing date	60 days
Expansion of board of director members, number of members | $ / shares	6
Minimum number of shares outstanding and unconverted, terms of stock or convertible securities issuance, approved written consent required (in shares) | shares	333