Income taxes - Reconciliation of income taxes (Details) - CAD ($) $ in Thousands	12 Months Ended
Jun. 30, 2019	Jun. 30, 2018
Income Taxes [Abstract]
Applicable tax rate	31.00%	31.00%
Income tax expense (recovery) based on combined federal and provincial tax rates of 31% (June 30, 2017 - 31%)	$ (25,391)	$ (1,664)
Share-based compensation	7	915
Non-taxable portion of capital gain	(4,768)	(1,024)
Tax rate differential	10,536	3,675
Non-controlling interest	(5,946)	(2,223)
Tax rate change on opening balance	0	2,120
Derecognition of Deferred Tax Assets	21,743	0
Other	113	(308)
(Recovery of) provision for income taxes	$ (3,706)	$ 1,491

Derecognition of Deferred Tax Assets

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Income Taxes [Abstract]

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Tax Effect Of Non-controlling Interest

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No definition available.

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Tax Effect Of Share-Based Compensation

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- Definition

The applicable income tax rate.

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The aggregate amount included in the determination of profit (loss) for the period in respect of current tax and deferred tax. [Refer: Current tax expense (income); Deferred tax expense (income)]

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The amount that represents the difference between the tax expense (income) and the product of the accounting profit multiplied by the applicable tax rate(s) that the entity does not separately disclose in the same statement or note. [Refer: Accounting profit; Applicable tax rate]

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The amount that represents the difference between the tax expense (income) and the product of the accounting profit multiplied by the applicable tax rate(s) that relates to changes in the tax rate. [Refer: Accounting profit]

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The amount that represents the difference between the tax expense (income) and the product of the accounting profit multiplied by the applicable tax rate(s) that relates to foreign tax rates. [Refer: Accounting profit]

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The amount that represents the difference between the tax expense (income) and the product of the accounting profit multiplied by the applicable tax rate(s) that relates to revenues that are exempt from taxation. [Refer: Accounting profit]

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The product of the accounting profit multiplied by the applicable tax rate(s). [Refer: Accounting profit; Applicable tax rate]

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