The interest rate on borrowings. [Refer: Borrowings]

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No definition available.

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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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The nominal or face amount of a financial instrument, used to calculate payments made on that instrument.

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The amount of trade payables and other payables. [Refer: Trade payables; Other payables]

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The amount of undrawn borrowing facilities that may be available for future operating activities and to settle capital commitments. [Refer: Capital commitments]

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Financial Instruments and Risk Management - Liquidity Risk (Details)	Dec. 31, 2020 CAD ($)	Dec. 31, 2020 USD ($)	Mar. 05, 2020 CAD ($)	Feb. 20, 2020 CAD ($)	Feb. 20, 2020 USD ($)	Feb. 05, 2020 USD ($)	Dec. 31, 2019 CAD ($)
Disclosure of nature and extent of risks arising from financial instruments [line items]
Undrawn borrowing facilities	$ 367,200,000
Financial derivatives	26,792,000						$ 8,668,000
Trade and other payables	155,955,000						207,454,000
Credit facilities	649,221,000						505,412,000
Long-term notes	1,132,868,000						1,328,175,000
Lease obligations	11,850,000						14,568,000
Notional amount	$ 664,700,000
8.75% Notes Due April 1, 2027
Disclosure of nature and extent of risks arising from financial instruments [line items]
Notional amount		$ 500,000,000				$ 500,000,000
8.75% Notes Due April 1, 2027 \| Fixed interest rate
Disclosure of nature and extent of risks arising from financial instruments [line items]
Borrowings, interest rate	8.75%	8.75%				8.75%
5.125% notes due June 1, 2021
Disclosure of nature and extent of risks arising from financial instruments [line items]
Notional amount		$ 400,000,000		$ 530,400,000	$ 400,000,000
5.125% notes due June 1, 2021 \| Fixed interest rate
Disclosure of nature and extent of risks arising from financial instruments [line items]
Borrowings, interest rate	5.125%	5.125%		5.125%	5.125%
6.625% notes due July 19, 2022
Disclosure of nature and extent of risks arising from financial instruments [line items]
Notional amount	$ 300,000,000		$ 300,000,000
6.625% notes due July 19, 2022 \| Fixed interest rate
Disclosure of nature and extent of risks arising from financial instruments [line items]
Borrowings, interest rate	6.625%	6.625%	6.625%
Liquidity risk
Disclosure of nature and extent of risks arising from financial instruments [line items]
Undrawn borrowing facilities	$ 367,200,000						523,800,000
Trade and other payables	155,955,000
Credit facilities	651,173,000
Long-term notes	1,147,950,000
Interest on long-term notes	446,854,000
Lease obligations	11,850,000
Financial liabilities	2,440,574,000
Less than 1 year
Disclosure of nature and extent of risks arising from financial instruments [line items]
Lease obligations	4,504,000						6,216,000
Less than 1 year \| Liquidity risk
Disclosure of nature and extent of risks arising from financial instruments [line items]
Financial derivatives	26,792,000
Trade and other payables	155,955,000
Credit facilities	0
Long-term notes	0
Interest on long-term notes	84,502,000
Lease obligations	4,504,000
Financial liabilities	271,753,000
1-3 years
Disclosure of nature and extent of risks arising from financial instruments [line items]
Lease obligations	4,302,000						7,748,000
1-3 years \| Liquidity risk
Disclosure of nature and extent of risks arising from financial instruments [line items]
Financial derivatives	0
Trade and other payables	0
Credit facilities	0
Long-term notes	0
Interest on long-term notes	169,004,000
Lease obligations	4,302,000
Financial liabilities	173,306,000
3-5 years
Disclosure of nature and extent of risks arising from financial instruments [line items]
Lease obligations	3,044,000						604,000
3-5 years \| Liquidity risk
Disclosure of nature and extent of risks arising from financial instruments [line items]
Financial derivatives	0
Trade and other payables	0
Credit facilities	651,173,000
Long-term notes	510,200,000
Interest on long-term notes	123,479,000
Lease obligations	3,044,000
Financial liabilities	1,287,896,000
Beyond 5 years
Disclosure of nature and extent of risks arising from financial instruments [line items]
Lease obligations	0						$ 0
Beyond 5 years \| Liquidity risk
Disclosure of nature and extent of risks arising from financial instruments [line items]
Financial derivatives	0
Trade and other payables	0
Credit facilities	0
Long-term notes	637,750,000
Interest on long-term notes	69,869,000
Lease obligations	0
Financial liabilities	$ 707,619,000