Capital Stock (Details) - USD ($)		1 Months Ended			3 Months Ended		6 Months Ended	9 Months Ended
	Dec. 09, 2016	Jun. 30, 2019	Jun. 30, 2018	Feb. 28, 2018	Sep. 30, 2019	Sep. 30, 2018	Jun. 30, 2019	Sep. 30, 2019	Sep. 30, 2018
Stock-based compensation disclosure
Stock compensation expense							$ 2,800,000
Stock options
Stock-based compensation disclosure
Stock options granted to directors (in shares)								7,340,000
2001 Non-Employee Director Stock Plan
Stock-based compensation disclosure
Stock compensation expense									$ 31,000
2001 Non-Employee Director Stock Plan | Retiring director
Stock-based compensation disclosure
Stock compensation expense			$ 72,000
Compensation Policy for Non-Employee Directors
Stock-based compensation disclosure
Stock compensation expense					$ 45,000	$ 101,000		$ 246,000	$ 258,000
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
Common stock issued to retiring directors (in shares)			95,497	77,012
Vesting period	1 year