Inventories of Crude Oil and Products (Detail) (CAD) In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Product Information [Line Items]
Crude oil	628	473
Petroleum products	340	284
Chemical products	54	60
Natural gas and other	8	10
Total inventories of crude oil and products	1,030	827

Carrying value of natural gas and other products.

No definition available.

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- Definition

Carrying value of petroleum products.

+ References

No definition available.

+ Details

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- Definition

Carrying amount as of the balance sheet date of solvents or substances produced by or used in a process to change the shape, form or composition of some related matter.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.6(a))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 6

-Subparagraph a

-Article 5

+ Details

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- Definition

Carrying amount as of the balance sheet date of petroleum or crude oil.

+ References

+ Details

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- Definition

Amount before valuation reserves of merchandise or goods held by the entity that are readily available for sale and items held by the entity which are partially complete or in the process of being readied for sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 6

-Subparagraph a

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.6(a)(1),(3))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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