Stockholders' Equity - Preferred Stock Issuances - Additional Information (Details) - USD ($)			9 Months Ended
	May 05, 2020	Jul. 11, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019	Aug. 19, 2019	Jun. 06, 2019
Stockholders Equity Note [Line Items]
Preferred stock, par value (in dollars per share)			$ 0.01		$ 0.01
Shares issued, par value per share			$ 0.01		$ 0.01
Offering price	$ 22,000,000		$ 19,377,000	$ 0
Warrant exercise price			$ 10.00
Deemed dividend for triggering of warrant down round feature			$ (55,000)
Preferred stock, shares outstanding (in shares)			21,473		41,517
Number of warrants outstanding (in shares)			4,362,373		1,826,608
2019 Warrants [Member]
Stockholders Equity Note [Line Items]
Offering price	$ 21,996,000
Warrant exercise price	$ 10.00				$ 23.04
Deemed dividend for triggering of warrant down round feature	$ 54,500
Number of warrants outstanding (in shares)			1,826,579
Series E Convertible Preferred Stock [Member] | July 2019 Private Placement [Member] | Securities Purchase Agreement [Member]
Stockholders Equity Note [Line Items]
Number of shares issued		20,000
Preferred stock, par value (in dollars per share)		$ 0.01
Shares issued, price per share		1,000
Shares issued, par value per share		$ 0.01
Series E Preferred Stock and Related Warrants [Member]
Stockholders Equity Note [Line Items]
Conversion price							$ 1,500
Series E Preferred Stock and Related Warrants [Member] | July 2019 Private Placement [Member]
Stockholders Equity Note [Line Items]
Debt and warrants exchanged for preferred stock		$ 11,800,000
Number of preferred stock and warrants issued upon conversion		11,500
Value of accounts payable exchanged		$ 100,000
Number of shares issued upon exchange of accounts payable		149
Number of shares issued upon exchange of investor waiver rights		923
Series E-1 Convertible Preferred Stock [Member] | August 2019 Private Placement [Member] | Securities Purchase Agreement [Member]
Stockholders Equity Note [Line Items]
Number of shares issued						9,510
Preferred stock, par value (in dollars per share)						$ 0.01
Shares issued, price per share						1,000
Shares issued, par value per share						$ 0.01
Preferred Stock [Member]
Stockholders Equity Note [Line Items]
Conversion price	$ 10.00				$ 23.04
Offering price	$ 21,996,000
Excess of the fair value of the common stock	$ 12,000,000