RELATED PARTY TRANSACTIONS (Details) - CAD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2024	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
RELATED PARTY TRANSACTIONS
Revenues	$ 16,217	$ 14,882	$ 11,336	$ 11,038	$ 11,298	$ 9,844	$ 10,432	$ 12,075	$ 53,473	$ 43,649	$ 53,309
Operating and administrative									9,427	8,600	8,219
Significantly Influenced Investees
RELATED PARTY TRANSACTIONS
Operating and administrative									637	625	503
Commodity costs									22	63	778
Gas distribution costs									147	140	136
Transportation and other services
RELATED PARTY TRANSACTIONS
Revenues									19,653	19,226	17,922
Transportation and other services | Significantly Influenced Investees
RELATED PARTY TRANSACTIONS
Revenues									181	169	185
Commodity sales
RELATED PARTY TRANSACTIONS
Revenues									27,018	18,981	29,150
Commodity sales | Significantly Influenced Investees
RELATED PARTY TRANSACTIONS
Revenues									0	0	51
Seaway Crude Pipeline System | Significantly Influenced Investees
RELATED PARTY TRANSACTIONS
Operating and administrative									650	632	495
Aux Sable Canada LP | Significantly Influenced Investees
RELATED PARTY TRANSACTIONS
Commodity costs									$ 0	$ 2	$ 571