Major Commitments and Contingencies (Guarantees and Indemnifications) (Details) - CAD ($)	Dec. 31, 2024	Dec. 31, 2023
Guarantee Obligations [Member]
Guarantees and indemnifications
Liability current carrying value	$ 0
Indemnification Agreement [Member]
Guarantees and indemnifications
Liability current carrying value	0
Performance Guarantee [Member] \| Committed Bilateral Letter of Credit Facilites [Member]
Guarantees and indemnifications
Outstanding letters of credit	329,000,000	$ 337,000,000
Maximum potential liability under guarantees	616,000,000	646,000,000
Performance Guarantee [Member] \| Uncommitted Bilateral Letter of Credit Facilities [Member]
Guarantees and indemnifications
Outstanding letters of credit	142,000,000	152,000,000
Performance Guarantee [Member] \| Surety and Other Bond [Member]
Guarantees and indemnifications
Liability current carrying value	145,000,000	157,000,000
Other Employee Benefit Liabilities and Workers' Compensation [Member]
Guarantees and indemnifications
Maximum potential liability under guarantees	571,000,000	603,000,000
Other Liabilities [Member]
Guarantees and indemnifications
Maximum potential liability under guarantees	$ 45,000,000	$ 43,000,000

No definition available.

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- Definition

The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482425/460-10-50-4

+ Details

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Period Type:	instant

- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482425/460-10-50-4

+ Details

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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