Warrants to Acquire Shares of Common Stock - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions		6 Months Ended
	Jan. 02, 2020	Jun. 30, 2020	Jan. 09, 2020	Mar. 06, 2019
Class of Warrant or Right [Line Items]
Common stock to be called by warrants (in shares)			818,900
Number of warrants exercised (in shares)		449,000
Series A Convertible Preferred
Class of Warrant or Right [Line Items]
Common stock to be called by warrants (in shares)				76,000
Warrant exercise price (in dollars per share)	$ 7.50			$ 70.00
Number of warrants exercised (in shares)		0
Warrants 2019
Class of Warrant or Right [Line Items]
Number of warrants exercised (in shares)	63,000
Warrants 2020
Class of Warrant or Right [Line Items]
Decrease (increase) in warrant fair value		$ 0.1