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Shareholders' Equity - Open Market Sale Agreement and Pre-funded Warrants and Common Shares - Public Offering (Details) - USD ($)						12 Months Ended
	Nov. 21, 2021	May 15, 2021	Oct. 22, 2020	Jul. 29, 2020	Jul. 23, 2020	Dec. 31, 2020
Class of Warrant or Right
Warrants exercise price		$ 0.01
Net proceeds	$ 250,000,000		$ 48,200,000			$ 24,917,000
Offering price						$ 48,153,000
ATM Program \| Maximum
Class of Warrant or Right
Offering price				$ 50,000,000
Pre Funded Warrant [Member]
Class of Warrant or Right
Warrants issued to purchase shares			4,761,903		6,655,131
Purchase price			$ 0.01		$ 3.7465
Warrants exercise price			$ 5.24		$ 0.01
Net proceeds					$ 24,800,000
Pre Funded Warrant [Member] \| Maximum
Class of Warrant or Right
Warrants issued to purchase shares		910,746
Purchase price		$ 5.48
Net proceeds		$ 5,000,000.0
Common Shares
Class of Warrant or Right
Number of shares issued during the period			5,095,897			5,095,897
Purchase price			$ 5.25
Offering price						$ 24,917,000