Financial and derivative instruments - Additional Information (Detail) $ in Millions	Dec. 31, 2019 CAD ($) bbl	Dec. 31, 2018 CAD ($) bbl
Financial Instruments And Derivatives [Line Items]
Fair value of collateral receivable	$ 6	$ 0
Long-term Debt, Fair Value	4,447	4,447
Fair value of derivative asset	0	31
Fair value of derivative liability	$ 2	$ 15
Product
Financial Instruments And Derivatives [Line Items]
Net notional forward long / (short) position of derivative instruments \| bbl	0	(340,000)
Crude Oil
Financial Instruments And Derivatives [Line Items]
Net notional forward long / (short) position of derivative instruments \| bbl	(590,000)	(350,000)

Derivative Instruments Not Designated As Hedging Instruments Asset At Carrying Value.

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- Definition

Derivative Instruments Not Designated As Hedging Instruments Liability At Carrying Value.

+ References

No definition available.

+ Details

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- Definition

Derivatives non monetary volume notional long and short position amount barrels of oil.

+ References

No definition available.

+ Details

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- Definition

Financial Instruments And Derivatives [Line Items]

+ References

No definition available.

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- Definition

Amount of right to receive cash collateral under master netting arrangements that have not been offset against derivative liabilities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226016-175313

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=d3e41678-113959

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (d)(2)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

+ Details

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

+ Details

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