Capital Stock (Details) - shares		1 Months Ended		3 Months Ended
	Dec. 09, 2016	Jun. 30, 2019	Jun. 30, 2018	Mar. 31, 2020
Stock options
Stock-based compensation disclosure
Stock options granted to directors (in shares)				5,740,000
Compensation Policy for Non-Employee Directors | Stock options
Stock-based compensation disclosure
Vesting period				1 year
Stock options granted to directors (in shares)		108,000	128,000
Compensation Policy for Non-Employee Directors | Deferred share units
Stock-based compensation disclosure
Vesting period	1 year