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Percentage change in currency rate.

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The amount of financial assets classified as derivative instruments. [Refer: Financial assets; Derivatives [member]]

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The amount of income associated with interest and other financing activities of the entity.

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The amount of assets that are: (a) cash; (b) an equity instrument of another entity; (c) a contractual right: (i) to receive cash or another financial asset from another entity; or (ii) to exchange financial assets or financial liabilities with another entity under conditions that are potentially favourable to the entity; or (d) a contract that will, or may be, settled in the entity’s own equity instruments and is: (i) a non-derivative for which the entity is, or may be, obliged to receive a variable number of the entity’s own equity instruments; or (ii) a derivative that will, or may be, settled other than by the exchange of a fixed amount of cash or another financial asset for a fixed number of the entity’s own equity instruments. For this purpose the entity’s own equity instruments do not include puttable financial instruments classified as equity instruments in accordance with paragraphs 16A-16B of IAS 32, instruments that impose on the entity an obligation to deliver to another party a pro rata share of the net assets of the entity only on liquidation and are classified as equity instruments in accordance with paragraphs 16C-16D of IAS 32, or instruments that are contracts for the future receipt or delivery of the entity’s own equity instruments. [Refer: Financial instruments, class [member]; Financial liabilities]

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The amount of liabilities that are: (a) a contractual obligation: (i) to deliver cash or another financial asset to another entity; or (ii) to exchange financial assets or financial liabilities with another entity under conditions that are potentially unfavourable to the entity; or (b) a contract that will, or may be, settled in the entity’s own equity instruments and is: (i) a non-derivative for which the entity is, or may be, obliged to deliver a variable number of the entity’s own equity instruments; or (ii) a derivative that will, or may be, settled other than by the exchange of a fixed amount of cash or another financial asset for a fixed number of the entity’s own equity instruments. For this purpose, rights, options or warrants to acquire a fixed number of the entity’s own equity instruments for a fixed amount of any currency are equity instruments if the entity offers the rights, options or warrants pro rata to all of its existing owners of the same class of its own non-derivative equity instruments. Also, for those purposes the entity’s own equity instruments do not include puttable financial instruments that are classified as equity instruments in accordance with paragraphs 16A-16B of IAS 32, instruments that impose on the entity an obligation to deliver to another party a pro rata share of the net assets of the entity only on liquidation and are classified as equity instruments in accordance with paragraphs 16C-16D of IAS 32, or instruments that are contracts for the future receipt or delivery of the entity’s own equity instruments. As an exception, an instrument that meets the definition of a financial liability is classified as an equity instrument if it has all the features and meets the conditions in paragraphs 16A-16B or paragraphs 16C-16D of IAS 32. [Refer: Financial instruments, class [member]; Financial assets; Derivatives [member]]

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The gains (losses) resulting from change in the fair value of derivatives recognised in profit or loss. [Refer: Derivatives [member]]

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The amount of short-term deposits held by the entity that are not classified as cash equivalents. [Refer: Cash equivalents]

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The amount due from customers for goods and services sold.

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Financial instruments - related risk management (Details) - CAD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Disclosure of detailed information about financial instruments [line items]
Financial assets	$ 1,237,825	$ 1,425,387
Financial liabilities	(1,241,874)	(1,203,910)
Gain (loss) on derivatives	36,577	32,269
Finance income	10,835	29,760
Disclosure of credit risk exposure [abstract]
Cash and cash equivalents	918,382	1,062,431	$ 711,528
Short-term investments	24,985	0
Derivative assets	$ 45,605	10,504
USD currency risk [member]
Disclosure of detailed information about financial instruments [line items]
Percentage increase or decrease in CAD$	5.00%
USD currency risk [member] \| Cash and cash equivalents [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets	$ 86,985
Gain (loss), foreign exchange	4,349
USD currency risk [member] \| Accounts receivable [Member]
Disclosure of detailed information about financial instruments [line items]
Financial assets	136,894
Gain (loss), foreign exchange	6,845
USD currency risk [member] \| Accounts Payable and Accrued Liabilities [Member]
Disclosure of detailed information about financial instruments [line items]
Financial liabilities	(72,576)
Gain (loss), foreign exchange	(3,629)
USD currency risk [member] \| Net foreign currency derivatives [Member]
Disclosure of detailed information about financial instruments [line items]
Financial assets	40,872
Gain (loss), foreign exchange	(38,811)
Credit risk [member]
Disclosure of credit risk exposure [abstract]
Cash and cash equivalents	918,382	1,062,431
Short-term investments	24,985	0
Accounts receivable	166,788	323,430
Derivative assets	$ 45,605	$ 10,504