Debt and Credit Facilities - Short-Term Debt (Details) - CAD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Debt and Credit Facilities
Short-term debt	$ 494	$ 2,807
Commercial paper
Debt and Credit Facilities
Short-term debt	494	2,807
Commercial paper \| Maximum
Debt and Credit Facilities
Commercial paper authorized to be issued	$ 5,000	$ 5,000
Term of debt	365 days	365 days
Commercial paper \| Weighted average
Debt and Credit Facilities
Interest rate	5.57%	4.93%

The interest rate on borrowings. [Refer: Borrowings]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

+ References

No definition available.

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- Definition

The amount of current borrowings. [Refer: Borrowings]

+ References

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

Represents the amount of commercial paper that is authorised to be issued.

+ References

No definition available.

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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