Other liabilities and deferred credits (Details) (CAD) In Millions, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Other liabilities and deferred credits [Line items]
Personal injury and other claims provisions, net of current portion (Note 17)	226	263
Stock-based incentives liability, net of current portion (Note 11)	180	162
Environmental provisions, net of current portion (Note 17)	89	116
Deferred credits and other	267	282
Total other liabilities and deferred credits	762	823

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This element reflects the non-current estimated ultimate cost of settling claims relating to workers compensation, personal injury and legal and other claims that have occurred on or before the balance sheet date.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Carrying value of the obligation (known or estimated) arising from requirements to perform activities to remediate one or more sites, payable after twelve months or beyond the next operating cycle if longer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 1

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

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-Section 50

-Paragraph 7

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 24

-Article 5

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

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-Subparagraph (d)(1)

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-Publisher AICPA

-Name Statement of Position (SOP)

-Number 96-1

-Paragraph 161, 163

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.24)

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

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- Definition

Aggregate carrying value as of the balance sheet date of the liabilities for stock option plans and other equity-based compensation arrangements payable after one year (or the operating cycle, if longer).

+ References

No definition available.

+ Details

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- Definition

Carrying amount as of the balance sheet date of unearned revenue or income, not otherwise specified in the taxonomy, which is expected to be taken into income after one year or beyond the normal operating cycle, if longer and noncurrent obligations not separately disclosed in the balance sheet (other liabilities, noncurrent).

+ References

No definition available.

+ Details

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- Definition

Aggregate carrying amount, as of the balance sheet date, of noncurrent obligations not separately disclosed in the balance sheet. Noncurrent liabilities are expected to be paid after one year (or the normal operating cycle, if longer).

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 24

-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 210.5-02.24)

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

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