VARIABLE INTEREST ENTITIES - Schedule of Assets and Liabilities of Consolidated VIEs (Details) - CAD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Assets
Cash and cash equivalents	$ 5,901	$ 861
Restricted cash	84	46
Other Assets, Current	2,440	3,255
Inventory	1,479	2,255
Current assets	14,399	12,147
Property, plant and equipment, net	104,641	104,460	$ 100,067
Long-term investments	16,793	15,936
Restricted long-term investments	717	593
Deferred amounts and other assets	8,041	9,542
Intangible assets, net	3,537	4,018
Total assets	180,317	179,608
Liabilities
Other current liabilities	5,659	5,220
Current liabilities	17,435	20,301
Long-term debt	74,715	72,939
Other long-term liabilities	8,653	9,189
Deferred income taxes	15,031	13,781
Liabilities	115,834	116,210
Variable Interest Entity, Primary Beneficiary
Assets
Cash and cash equivalents	442	426
Restricted cash	9	12
Trade receivables and unbilled revenue	144	185
Other Assets, Current	8	14
Inventory	11	12
Current assets	619	672
Property, plant and equipment, net	7,105	7,707
Long-term investments	14	14
Restricted long-term investments	106	98
Deferred amounts and other assets	148	158
Intangible assets, net	84	102
Total assets	8,076	8,751
Liabilities
Other current liabilities	145	152
Current liabilities	232	272
Long-term debt	1	0
Other long-term liabilities	971	859
Deferred income taxes	5	5
Liabilities	1,209	1,136
Net assets	6,867	7,615
Variable Interest Entity, Primary Beneficiary | Related Party
Assets
Accounts receivable from affiliates	5	23
Liabilities
Trade payables and accrued liabilities	4	21
Variable Interest Entity, Primary Beneficiary | Nonrelated Party
Liabilities
Trade payables and accrued liabilities	$ 83	$ 99