Share Capital, Option Plans and Share-Based Payments - RSU's, DSU's and ESPP (Details) - USD ($)	3 Months Ended	9 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Mar. 31, 2018
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted (in shares)	0	0	0	4,464
Award vesting period			3 years
Stock issued (in shares)	10,000	20,000	18,794	94,792
Stock issued	$ 300,000	$ 400,000	$ 600,000	$ 2,000,000.0
Deferred Stock Units (DSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted (in shares)	3,406	3,037	96,748	83,846
Stock issued (in shares)	51,794	0	51,794	0
Stock issued	$ 2,000,000.0	$ 0	$ 2,000,000	$ 0
Employee Share Purchase Plan (ESPP)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards purchase price discount			15.00%
Common shares eligible for issuance (in shares)	187,705	201,726	523,867	540,343
Cash received from employee stock purchase plan	$ 6,100,000	$ 5,800,000	$ 16,200,000	$ 15,900,000

Cash collected to be used to purchase Common Stock in future periods

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price Discount

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No definition available.

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Share-based Compensation Arrangement by Share-based Payment Award, Shares Eligible for Issuance

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards.

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Aggregate value of stock related to Restricted Stock Awards issued during the period.

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