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- Definition

Commitments In Relation To Joint Ventures, Percentage Pro Rata Share Of Monthly Debt Cost

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- Definition

Commitments In Relation To Joint Ventures, Term

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- Definition

Joint Venture, Processing Agreement, Barrels Of Bitumen Feedstock Processed Per Day

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- Definition

Joint Venture, Processing Agreement, Barrels Of Bitumen Feedstock Processed Per Day, Portion Related To Company

+ References

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- Definition

Joint Venture, Processing Agreement, Barrels Of Bitumen Feedstock Processed Per Day, Portion Related To Others

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- Definition

Joint Venture, Processing Agreement, Term

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- Definition

Line Of Credit Facility, Maximum Borrowing Capacity1

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- Definition

Proceeds Received For Debt Instruments Held

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No definition available.

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- Definition

Recognized Share Of Losses Of Joint Ventures

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No definition available.

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- Definition

The amount of outstanding funds that the entity is obligated to repay.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

The interest rate on borrowings. [Refer: Borrowings]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

The cumulative amount of the unrecognised share of losses of joint ventures if the entity has stopped recognising its share of losses when applying the equity method. [Refer: Joint ventures [member]; Unrecognised share of losses of joint ventures]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The amount of instruments representing indebtedness held by the entity.

+ References

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- Definition

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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- Definition

The proportion of ownership interest in a joint venture attributable to the entity. [Refer: Joint ventures [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Number 27
-IssueDate 2020-01-01
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- Definition

The proportion of the voting rights in a joint venture held by the entity. [Refer: Joint ventures [member]]

+ References

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- Definition

The amount of the unrecognised share of joint ventures' losses if the entity has stopped recognising its share of losses when applying the equity method. [Refer: Joint ventures [member]]

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Other Long-Term Assets - Narrative (Details) $ in Millions	12 Months Ended
Other Long-Term Assets - Narrative (Details) $ in Millions	Dec. 31, 2020 CAD ($) bbl	Dec. 31, 2019 CAD ($)	Dec. 31, 2018 CAD ($)	Mar. 24, 2021 CAD ($)
Disclosure of joint ventures [line items]
North West Redwater Partnership subordinated debt	$ 555	$ 652
Borrowings	$ 21,453	20,982
North West Redwater Partnership
Disclosure of joint ventures [line items]
Company's voting percent interest in joint venture	50.00%
North West Redwater Partnership subordinated debt	$ 555	652
North West Redwater Partnership subordinated debt, term	10 years
North West Redwater Partnership subordinated debt, interest rate	6.00%
North West Redwater Partnership subordinated debt, proceeds received	$ 124
Processing agreement, barrels of bitumen feedstock per day \| bbl	50,000
Processing agreement, barrels of bitumen feedstock per date for the Company \| bbl	12,500
Processing agreement, barrels of bitumen feedstock per date for others \| bbl	37,500
Percent of pro rata share of debt company has committed paying to joint venture	25.00%
Term of commitment to joint venture	30 years
Unrecognised share of losses of joint ventures	$ 94	59
Recognized share of losses of joint ventures		287	$ 5
Cumulative unrecognised share of losses of joint ventures	$ 153	59
Company's ownership interest in joint venture	50.00%
Non-revolving term credit facility maturing February 2021
Disclosure of joint ventures [line items]
Maximum credit facility	$ 750
North West Redwater Partnership \| North West Redwater Partnership
Disclosure of joint ventures [line items]
Processing agreement, barrels of bitumen feedstock per day \| bbl	50,000
Processing agreement term	30 years
North West Redwater Partnership \| Syndicated credit facility \| North West Redwater Partnership
Disclosure of joint ventures [line items]
Maximum credit facility	$ 3,500
Borrowings	2,866	2,715
North West Redwater Partnership \| Non-revolving term credit facility maturing February 2021 \| North West Redwater Partnership
Disclosure of joint ventures [line items]
Maximum credit facility	1,500	$ 1,500		$ 1,500
Major Borrowings Transactions \| North West Redwater Partnership \| Syndicated credit facility \| North West Redwater Partnership
Disclosure of joint ventures [line items]
Maximum credit facility	$ 2,000