The aggregate difference between the fair value at initial recognition and the transaction price for financial instruments that is yet to be recognised in profit or loss. [Refer: Financial instruments, class [member]]

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- Definition

The spot exchange rate at the end of the reporting period. Exchange rate is the ratio of exchange for two currencies. Spot exchange rate is the exchange rate for immediate delivery.

+ References

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

+ References

No definition available.

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The increase (decrease) in the aggregate difference between the fair value at initial recognition and the transaction price of financial instruments yet to be recognised in profit or loss resulting from amounts recognised in profit or loss. [Refer: Aggregate difference between fair value at initial recognition and transaction price yet to be recognised in profit or loss; Financial instruments, class [member]]

+ References

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The increase (decrease) in the aggregate difference between the fair value at initial recognition and the transaction price of financial instruments yet to be recognised in other comprehensive income (loss) resulting from amounts recognised in other comprehensive income (loss).

+ References

No definition available.

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Financial risk management (Schedule of Currency Risks) (Details) - Currency risk [Member] MXN in Thousands, CAD in Thousands	12 Months Ended
	Dec. 31, 2017 CAD CAD / $ MXN / $	Dec. 31, 2017 MXN	Dec. 31, 2017 MXN CAD / $ MXN / $
Canadian Dollar [Member]
Disclosure of nature and extent of risks arising from financial instruments [line items]
Approximate impact of exchange rate fluctuations on net loss \| CAD	CAD 732
Approximate impact of exchange rate fluctuations on other comprehensive loss \| CAD	CAD (93)
Foreign exchange rates \| CAD / $	1.25		1.25
Mexican Peso [Member]
Disclosure of nature and extent of risks arising from financial instruments [line items]
Approximate impact of exchange rate fluctuations on net loss \| MXN		MXN 850
Approximate impact of exchange rate fluctuations on other comprehensive loss \| MXN		MXN 110
Foreign exchange rates \| MXN / $	19.74		19.74
Cash and Cash Equivalents [Member] \| Canadian Dollar [Member]
Disclosure of nature and extent of risks arising from financial instruments [line items]
Risk from currency fluctuations yet to be recognized in net earnings or other comprehensive income \| CAD	CAD 1,436
Cash and Cash Equivalents [Member] \| Mexican Peso [Member]
Disclosure of nature and extent of risks arising from financial instruments [line items]
Risk from currency fluctuations yet to be recognized in net earnings or other comprehensive income \| MXN			MXN 1,681
Trade and other receivables [Member] \| Canadian Dollar [Member]
Disclosure of nature and extent of risks arising from financial instruments [line items]
Risk from currency fluctuations yet to be recognized in net earnings or other comprehensive income \| CAD	19
Trade and other receivables [Member] \| Mexican Peso [Member]
Disclosure of nature and extent of risks arising from financial instruments [line items]
Risk from currency fluctuations yet to be recognized in net earnings or other comprehensive income \| MXN			2,814
Trade and Other Payables [Member] \| Canadian Dollar [Member]
Disclosure of nature and extent of risks arising from financial instruments [line items]
Risk from currency fluctuations yet to be recognized in net earnings or other comprehensive income \| CAD	CAD 1,831
Trade and Other Payables [Member] \| Mexican Peso [Member]
Disclosure of nature and extent of risks arising from financial instruments [line items]
Risk from currency fluctuations yet to be recognized in net earnings or other comprehensive income \| MXN			MXN 4,385