Common Shares - Summary Of Deferred Share Units Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended	12 Months Ended
May 31, 2019	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated Share-based Compensation Expense		$ 390	$ 51
Deferred Stock Units (DSU) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested, Number of units, beginning of period (in shares)		366,000
Granted, Number of units (in shares)	360,000	360,000		366,000
Unvested, Number of units, end of period (in shares)		726,000		366,000
Unvested, weighted average fair value, beginning of year (in dollars per share)		$ 0.57
Granted, Weighted average fair value (in dollars per share)		0.58		$ 0.57
Unvested, weighted average fair value, end of year (in dollars per share)		$ 0.57		$ 0.57
Allocated Share-based Compensation Expense	$ 209	$ 209

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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