Common Stock and Preferred Stock (Converted into Common Stock) - Registered Direct Offering (Details) - USD ($) $ / shares in Units, $ in Millions	Jun. 12, 2020	Jun. 10, 2020	Apr. 27, 2020	Apr. 23, 2020
Letter Agreement
Class of Stock [Line Items]
Cash fee, percent of gross proceeds				6.50%
Securities Purchase Agreement
Class of Stock [Line Items]
Shares issued in private placement transaction (in shares)		2,175,000		1,764,706
Sale of stock, price per share (in dollars per share)		$ 11.40		$ 8.50
Proceeds from issuance of common stock		$ 25.0		$ 15.0
Period in which company cannot issue additional common stock		60 days		75 days
The Offering
Class of Stock [Line Items]
Proceeds from issuance of common stock	$ 23.0		$ 13.9
Placement Agency Agreement [Member]
Class of Stock [Line Items]
Shares issued in private placement transaction (in shares)		2,175,000