Amount of foreign forward exchange contract.

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Availability under committed credit facility.

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Base shelf prospectus capacity.

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- Definition

Foreign exchange contracts outstanding.

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No definition available.

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Number of derivative counterparties with net settlement positions greater than ten percent.

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No definition available.

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Percentage of credit exposures using external credit grading system.

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No definition available.

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Target debt to adjusted earnings before interest taxes depreciation depletion and amortization ratio.

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No definition available.

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Unwound amount.

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No definition available.

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- Definition

The amount of cash on hand and demand deposits, along with short-term, highly liquid investments that are readily convertible to known amounts of cash and that are subject to an insignificant risk of changes in value. [Refer: Cash; Cash equivalents]

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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.

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No definition available.

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The rate of expected credit losses, calculated as percentage of the gross carrying amount. Expected credit losses are the weighted average of credit losses with the respective risks of a default occurring as the weights.

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The gain (loss) recognised on designation of a financial instrument, or a proportion of it, as measured at fair value through profit or loss, because a credit derivative is used to manage the credit risk of that financial instrument. [Refer: Credit risk [member]; Derivatives [member]; Financial instruments, class [member]]

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The amount of exchange differences recognised in profit or loss that arise from foreign currency transactions, excluding those arising on financial instruments measured at fair value through profit or loss in accordance with IFRS 9. [Refer: At fair value [member]; Financial instruments, class [member]]

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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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Risk Management - Additional Information (Detail) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2018 CAD ($)	Dec. 31, 2018 CAD ($)	Dec. 31, 2017 CAD ($)	Dec. 31, 2016 CAD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2015 CAD ($)
Disclosure of Nature and Extent of Risks Arising from Financial Instruments [Line Items]
Notional Amount					$ 6,774,000,000	$ 7,650,000,000
Foreign exchange contracts outstanding					45,000,000
Increase decrease to earnings from change in foreign exchange rate on foreign exchange contracts		$ (854,000)	$ 812,000	$ 198,000
Amount of Foreign Forward Exchange Contract	$ 4,000	4,000
Cash and cash equivalents	781,000	781,000	$ 610,000	$ 3,720,000			$ 4,105,000
Committed Credit Facility [member]
Disclosure of Nature and Extent of Risks Arising from Financial Instruments [Line Items]
Cash and cash equivalents	781,000	781,000
Available on committed credit facility	4,500,000	$ 4,500,000
Top of range [Member]
Disclosure of Nature and Extent of Risks Arising from Financial Instruments [Line Items]
Target debt to adjusted EBITDA ratio		200.00%
Liquidity risk [member] \| Top of range [Member] \| Base Shelf Prospectus [Member]
Disclosure of Nature and Extent of Risks Arising from Financial Instruments [Line Items]
Shelf prospectus amount					4,600,000,000
Foreign Exchange Contracts [Member]
Disclosure of Nature and Extent of Risks Arising from Financial Instruments [Line Items]
Increase decrease to earnings from change in foreign exchange rate on foreign exchange contracts		$ 50
Interest rate swap contract [Member]
Disclosure of Nature and Extent of Risks Arising from Financial Instruments [Line Items]
Notional Amount					$ 150,000,000	$ 400,000,000
Unwound amount	250,000
Risk management gain	$ 23,000
Trade receivables [member] \| Credit risk [member] \| Investment grade counterparties [member]
Disclosure of Nature and Extent of Risks Arising from Financial Instruments [Line Items]
Percent of accounts receivable held with investment grade counterparties	90.00%	90.00%	89.00%		90.00%	89.00%
Number of investment grade counterparties accounted for more than 10% in accounts receivable	1	1	3		1	3
Average expected credit loss rate	0.40%	0.40%			0.40%