REGULATORY MATTERS - Liquids Pipelines (Narrative) (Details) - CAD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Public Utilities, General Disclosures [Line Items]
Total regulatory asset	$ 7,619	$ 5,707
Canadian Mainline
Public Utilities, General Disclosures [Line Items]
Total regulatory asset	$ 2,000	$ 1,900

The amount for the individual regulatory asset as itemized in a table of regulatory assets as of the end of the period.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 980
-SubTopic 340
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478742/980-340-50-1

Name:	us-gaap_RegulatoryAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant