Commitments and Contingencies (Details) CAD in Thousands, $ in Thousands	3 Months Ended
	Sep. 30, 2016 USD ($) Plan	Sep. 30, 2015 USD ($)	Sep. 30, 2016 CAD	Jun. 30, 2016 USD ($)	Jun. 30, 2016 CAD
Letters of Credit [Abstract]
Letters of credit issued	$ 42,000			$ 42,800
Number of closed noncontributory defined benefit pension plans | Plan	3
Government Grants and Loans [Abstract]
Weighted average borrowing rate of government loans	6.40%		6.40%
Loans	$ 183		CAD 241	185	CAD 241
Grants - Received	68,078		89,298	68,643	89,298
Grants - Future advances	23,954		31,421	24,153	31,421
Total grants	$ 92,032		CAD 120,719	$ 92,796	CAD 120,719
Capital Leases [Abstract]
Weighted average remaining term	35 years
Weighted average interest rate	9.90%
Other [Abstract]
Payments for forestry licenses and land leases	$ 100	$ 100
Minimum [Member]
Other [Abstract]
Percentage of defined gross revenue	1.50%
Maximum [Member]
Other [Abstract]
Percentage of defined gross revenue	4.00%