Stockholders' Equity - Sales Agreement (Details) - USD ($) $ in Thousands		5 Months Ended	12 Months Ended
	Jul. 31, 2017	Dec. 31, 2017	Dec. 31, 2019
Equity [Abstract]
Stock issued (shares)	3,243,882	10,314,250	221,529
Proceeds Received (Net of Broker Commissions and Fees )	$ 23,745	$ 104,527	$ 1,814