Note 14 - Financial Instruments - Changes in Allowance for Doubtful Accounts (Details) - CAD ($) $ in Thousands	12 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Statement Line Items [Line Items]
Balance, beginning of year	$ 60,121	$ 49,431
Bad debt expense	192,202	56,331
Bad debts written off	(90,231)	(41,802)
Adjustment from IFRS 9 adoption	23,636
Foreign exchange	(3,363)	(3,808)
Balance, end of year	$ 182,375	$ 60,121

The amount of additional allowance for credit losses of financial assets recognised in profit or loss. [Refer: Allowance account for credit losses of financial assets]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Note Expiry date 2018-01-01
-Name IFRS
-Number 7
-IssueDate 2017-01-01
-Paragraph 16
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-02&anchor=para_16&doctype=Standard&book=B
-URIDate 2017-03-09

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- Definition

The amount of an allowance account used to record impairments to financial assets due to credit losses. [Refer: Financial assets]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2018-01-01
-Name IFRS
-Number 7
-IssueDate 2017-01-01
-Paragraph 16
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-02&anchor=para_16&doctype=Standard&book=B
-URIDate 2017-03-09

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- Definition

The increase (decrease) in an allowance account for credit losses of financial assets resulting from the net exchange differences arising when the financial statements are translated from the functional currency into a different presentation currency, including the translation of a foreign operation into the presentation currency of the reporting entity. [Refer: Allowance account for credit losses of financial assets]

+ References

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- Definition

The decrease in an allowance account for credit losses of financial assets resulting from the utilisation of the allowance. [Refer: Allowance account for credit losses of financial assets]

+ References

+ Details

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- Definition

The increase (decrease) in the allowance account for credit losses of financial assets resulting from adoption of new accounting policy.

+ References

No definition available.

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- References

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