For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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SIGNIFICANT ACCOUNTING POLICIES - Revenue Recognition (Details) - CAD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Disaggregation of Revenue [Line Items]
Revenue recognized	$ 166
Largest Non-Affiliated Customer \| Sales Revenue, Net \| Customer Concentration Risk
Disaggregation of Revenue [Line Items]
Concentration (percent)		13.50%	13.60%
Transportation revenue
Disaggregation of Revenue [Line Items]
Revenue recognized	$ 238	$ 127	$ 292