Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2018	Dec. 31, 2017
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized	120,000,000	120,000,000
Common stock, shares issued	16,608,512	9,792,497
Common stock, shares outstanding	16,608,512	9,792,497
Convertible preferred stock
Convertible preferred stock, par/stated value (in dollars per share)	$ 0.0001	$ 0.0001
Convertible preferred stock, shares authorized	20,000,000	20,000,000
Series A convertible preferred stock
Convertible preferred stock, par/stated value (in dollars per share)	$ 10	$ 10
Convertible preferred stock, shares issued	85,581	104,013
Convertible preferred stock, shares outstanding	85,581	104,013
Series C convertible preferred stock
Convertible preferred stock, par/stated value (in dollars per share)	$ 1,000	$ 1,000
Convertible preferred stock, shares issued	1,974	0
Convertible preferred stock, shares outstanding	1,974	0