Subsequent events - Additional Information (Detail) - Subsequent Event [Member] - Purdue Pharma [Member] - Belbuca [Member] - Collaborative Arrangement, Product [Member]	Jul. 12, 2017 CAD
Subsequent Event [Line Items]
Upfront and potential milestones payable	CAD 1,500,000
Maximum [Member]
Subsequent Event [Line Items]
Upfront and potential milestones payable	CAD 4,500,000

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

No definition available.

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Period Type:	duration