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Note 2 - Revision of Previously Issued Financial Statements for Immaterial Misstatements (Details Textual) $ in Millions | 3 Months Ended |
--- | --- | ---
Sep. 30, 2018 USD ($) | Jun. 01, 2013
Canada, Dollars |  |
Foreign Currency Exchange Rate, Translation |  | 0.9646
Understatement of Accumulated Depreciation, Depletion and Amortization [Member] | Period from June 01, 2013 Through June 30, 2018 [Member] |  |
Prior Period Reclassification Adjustment | $ 35.5 |
Overstatement of Accumulated Depreciation, Depletion and Amortization [Member] | Period from June 01, 2013 Through June 30, 2018 [Member] |  |
Prior Period Reclassification Adjustment | $ 14.2 |

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- Definition Foreign exchange rate used to translate amounts denominated in functional currency to reporting currency. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 30 -Section S99 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6897108&loc=SL6897125-166521 + Details
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