Contingencies and Commitments (Details)			12 Months Ended
	Jul. 16, 2019 CAD ($)	Jul. 16, 2019 USD ($)	Dec. 31, 2020 Spill BargeSlip Company	May 10, 2019 Vessel	Mar. 22, 2014 Vessel TankBarge
Loss Contingency [Abstract]
Loss contingency, settlement charges	$ 2,900,000	$ 2,200,000
Struck by LPG Tanker, the Genesis River [Member]
Loss Contingency [Abstract]
Number of vessels involved in collision				2
Collision with M/S Summer Wind [Member]
Loss Contingency [Abstract]
Number of vessels involved in collision					2
Number of vessels damaged in collision resulting in fuel oil discharge | TankBarge					1
Portland Harbor Superfund Site [Member]
Site Contingency [Line Items]
Number of other companies also named as Potentially Responsible Parties ("PRPs") | Company			250
Number of spills | Spill			4
SBA Shipyard Site [Member]
Site Contingency [Line Items]
Number of barge slips | BargeSlip			3