Financial Instruments - Summary of Valuation Techniques and Significant Unobservable Inputs in Fair Value Measurement of Level 3 Financial Instruments (Details) - Level 3	12 Months Ended
Mar. 31, 2018
JWC Warrants
Disclosure Of Financial Instruments [Line Items]
Valuation techniques	Black-Scholes option pricing model
Significant unobservable inputs	Share price
Relationship of unobservable inputs to fair value	Increase or decrease in share price will result in an increase or decrease in fair value
JWC Shares
Disclosure Of Financial Instruments [Line Items]
Valuation techniques	Market approach
Significant unobservable inputs	Share price
Relationship of unobservable inputs to fair value	Increase or decrease in share price will result in an increase or decrease in fair value
HydRx Shares
Disclosure Of Financial Instruments [Line Items]
Valuation techniques	Market approach
Significant unobservable inputs	Share price
Relationship of unobservable inputs to fair value	Increase or decrease in share price will result in an increase or decrease in fair value
HydRx Warrants
Disclosure Of Financial Instruments [Line Items]
Valuation techniques	Black-Scholes option pricing model
Significant unobservable inputs	Share price
Relationship of unobservable inputs to fair value	Increase or decrease in share price will result in an increase or decrease in fair value
Agripharm Warrant
Disclosure Of Financial Instruments [Line Items]
Valuation techniques	Black-Scholes option pricing model
Significant unobservable inputs	Share price
Relationship of unobservable inputs to fair value	Increase or decrease in share price will result in an increase or decrease in fair value
BC Tweed Call Option Liability
Disclosure Of Financial Instruments [Line Items]
Valuation techniques	Market approach
Significant unobservable inputs	Appraised value of property
Relationship of unobservable inputs to fair value	Increase or decrease in value will result in a increase or decrease in fair value
BC Tweed and Vert Mirabel Put Liability
Disclosure Of Financial Instruments [Line Items]
Valuation techniques	Discounted cash flow
Significant unobservable inputs	Discount rate
Relationship of unobservable inputs to fair value	Increase or decrease in discount rate will result in a decrease or increase in fair value
BC Tweed and Vert Mirabel Put Liability
Disclosure Of Financial Instruments [Line Items]
Valuation techniques	Discounted cash flow
Significant unobservable inputs	Future wholesale price and production levels
Relationship of unobservable inputs to fair value	Increase in future wholesale price and production levels will result in an increase in fair value

The description of inputs used in the fair value measurement of assets. Inputs are the assumptions that market participants would use when pricing the asset, including assumptions about risk such as the risk inherent in a particular valuation technique used to measure fair value (such as a pricing model) and the risk inherent in the inputs to the valuation technique.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 13
-IssueDate 2017-01-01
-Paragraph 93
-Subparagraph d
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-URIDate 2017-03-09

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The description of inputs used in the fair value measurement of liabilities. Inputs are the assumptions that market participants would use when pricing the liability, including assumptions about risk such as the risk inherent in a particular valuation technique used to measure fair value (such as a pricing model) and the risk inherent in the inputs to the valuation technique.

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The description of the sensitivity of the fair value measurement of assets to changes in unobservable inputs if a change to those inputs might result in a higher or lower fair value measurement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 13
-IssueDate 2017-01-01
-Paragraph 93
-Subparagraph h
-Clause i
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=13&date=2017-03-01&anchor=para_93_h_i&doctype=Standard
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The description of the sensitivity of the fair value measurement of liabilities to changes in unobservable inputs if a change in those inputs to a different amount might result in a higher or lower fair value measurement.

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The description of the valuation techniques (for example, the market approach, cost approach and income approach) used for the fair value measurement of assets. [Refer: Valuation techniques [member]; Cost approach [member]; Income approach [member]; Market approach [member]]

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