LONG-TERM INVESTMENTS - Summary of Combined Financial Information (Details) - CAD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Income statement information
Revenues (Note 4)	$ 13,424	$ 11,573	$ 13,215	$ 15,097	$ 12,470	$ 11,466	$ 10,948	$ 12,187	$ 53,309	$ 47,071	$ 39,087
Earnings	(1,109)	1,383	607	2,057	1,965	814	1,521	2,014	2,938	6,314	3,416
Earnings/(loss) attributable to controlling interests	(983)	$ 1,362	$ 595	$ 2,029	1,933	$ 780	$ 1,484	$ 1,992	3,003	6,189	3,363
Balance sheet information
Current assets	12,147				8,959				12,147	8,959
Current liabilities	20,301				18,229				20,301	18,229
Noncontrolling interests	3,511				2,542				3,511	2,542
Unconsolidated equity method investments
Income statement information
Revenues (Note 4)									27,043	20,021	14,096
Operating expenses									23,043	16,706	12,411
Earnings									4,334	3,022	2,324
Earnings/(loss) attributable to controlling interests									2,056	1,711	$ 1,136
Balance sheet information
Current assets	4,196				3,639				4,196	3,639
Non-current assets	53,405				44,863				53,405	44,863
Current liabilities	4,843				3,741				4,843	3,741
Non-current liabilities	18,595				16,979				18,595	16,979
Noncontrolling interests	$ 3,785				$ 3,786				$ 3,785	$ 3,786