DEBT AND CREDIT FACILITIES - Short Term Debt Summary (Details) - CAD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
DEBT AND CREDIT FACILITIES
Commercial papers issued	$ 1,284	$ 3,566
Interest rate	5.00%	4.80%
Commercial paper
DEBT AND CREDIT FACILITIES
Commercial papers issued	$ 1,284	$ 3,566
Commercial paper \| Maximum
DEBT AND CREDIT FACILITIES
Commercial paper authorized to be issued	$ 5,000
Term of debt	365 days
Commercial paper \| Weighted average
DEBT AND CREDIT FACILITIES
Interest rate	0.33%	0.39%

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

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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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