Common Stock (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2020	Jun. 30, 2020	Jun. 30, 2019
Subsidiary, Sale of Stock [Line Items]
Warrants issued in transaction (in shares)	1,914,280
Pre-funded warrants outstanding (in shares)	3,164,280	3,164,280	3,164,280
Payments of stock issuance costs			$ 10,100
Proceeds from issuance of common stock			$ 150,100
Underwritten Offering
Subsidiary, Sale of Stock [Line Items]
Number of shares issued in transaction (in shares)		28,503,220
Sale of stock price (in dollars per share)	$ 4.100	$ 4.100	$ 4.100
Proceeds from issuance of common stock			$ 116,883	$ 0
Underwritten Offering, Underwriters
Subsidiary, Sale of Stock [Line Items]
Sale of stock price (in dollars per share)	$ 3.854	3.854	$ 3.854
Private Placement
Subsidiary, Sale of Stock [Line Items]
Number of shares issued in transaction (in shares)	8,649,453
Exercise price of pre-funded warrants (in dollars per share)	$ 4.099	4.099	$ 4.099
Proceeds from issuance of common stock			$ 33,237	$ 0
Private Placement, Underwriters
Subsidiary, Sale of Stock [Line Items]
Exercise price of pre-funded warrants (in dollars per share)	$ 3.853	$ 3.853	$ 3.853