ACQUISITIONS AND DISPOSITIONS - Schedule of Supplemental Pro Forma Consolidated Financial Information (Details) - CAD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Questar Gas Company
Business Acquisition [Line Items]
Operating revenues	$ 14,882	$ 10,040	$ 38,471	$ 33,885
Earnings attributable to common shareholders	1,293	501	4,695	4,153
Pro forma interest expense		18		70
Pro forma interest expense, net of tax		14		52
EOG Acquisition
Business Acquisition [Line Items]
Operating revenues	14,882	10,131	37,568	33,375
Earnings attributable to common shareholders	1,296	625	4,614	4,266
Pro forma interest expense		26		100
Pro forma interest expense, net of tax		20		77
PSNC Acquisation
Business Acquisition [Line Items]
Operating revenues	15,010	9,949	37,921	33,038
Earnings attributable to common shareholders	$ 1,276	506	$ 4,655	4,173
Pro forma interest expense		12		48
Pro forma interest expense, net of tax		$ 9		$ 37