Nature of Business and Basis of Presentation - Additional Information (Details) $ / shares in Units, $ in Thousands, $ in Millions		1 Months Ended
	Dec. 07, 2020 USD ($)	Feb. 28, 2021 USD ($)	Dec. 31, 2020 USD ($) $ / shares	Apr. 30, 2021 USD ($)	Dec. 17, 2020 USD ($)	Dec. 17, 2020 CAD ($)	Oct. 31, 2020 USD ($)
Nature Of Business And Basis Of Presentation [Line Items]
Cash and cash equivalents, unrestricted				$ 139,086			$ 149,867
Underwritten Offering Shares | $ / shares			$ 25.0
Net proceeds from underwriting shares after deducting underwriting discounts and commissions			$ 156,400
Unrestricted cash				$ 47,500
Enbridge Inc. [Member] | Series 1 Preferred Shares [Member]
Nature Of Business And Basis Of Presentation [Line Items]
Related Party Transaction, Due from (to) Related Party					$ 21,500	$ 27.4
Sr. Secured Debt [Member]
Nature Of Business And Basis Of Presentation [Line Items]
Settlement of outstanding principal payment and interest	$ 87,300
Unrestricted cash	$ 11,200
Liberty Bank Promissory Note (PPP Note) [Member]
Nature Of Business And Basis Of Presentation [Line Items]
Repayments of debt		$ 6,500