v3.26.1
REVENUE - Schedule of Major Products and Services (Details) - CAD ($)
$ in Millions
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers $ 6,592 $ 6,511 $ 15,560 $ 15,288
Revenue not from contract with customers 0 0 0 0
Total revenue 29,318 14,876 51,675 33,378
Liquids Pipelines        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 2,786 2,970 5,643 6,143
Gas Transmission        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 1,671 1,539 3,367 3,216
Gas Distribution and Storage        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 2,058 1,950 6,396 5,835
Renewable Power Generation        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 77 52 154 94
Transportation revenue        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 4,255 4,307 8,584 8,954
Storage and other revenue        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 386 389 790 787
Gas distribution sales        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 1,830 1,735 5,943 5,401
Electricity revenue        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 77 52 154 94
Commodity sales        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 44 28 89 52
Revenue not from contract with customers 22,541 8,096 35,688 17,621
Other Revenue        
Disaggregation of Revenue [Line Items]        
Revenue not from contract with customers 185 269 427 469
Business Segments        
Disaggregation of Revenue [Line Items]        
Total revenue 29,186 14,602 51,011 32,577
Business Segments | Liquids Pipelines        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 2,786 2,970 5,643 6,143
Total revenue 25,221 10,837 40,683 23,021
Business Segments | Gas Transmission        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 1,671 1,539 3,367 3,216
Total revenue 1,720 1,604 3,501 3,319
Business Segments | Gas Distribution and Storage        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 2,058 1,950 6,396 5,835
Total revenue 2,081 2,016 6,489 5,972
Business Segments | Renewable Power Generation        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 77 52 154 94
Total revenue 164 145 338 265
Business Segments | Transportation revenue | Liquids Pipelines        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 2,720 2,895 5,515 6,000
Business Segments | Transportation revenue | Gas Transmission        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 1,462 1,349 2,933 2,829
Business Segments | Transportation revenue | Gas Distribution and Storage        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 73 63 136 125
Business Segments | Transportation revenue | Renewable Power Generation        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
Business Segments | Storage and other revenue | Liquids Pipelines        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 66 75 128 143
Business Segments | Storage and other revenue | Gas Transmission        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 173 162 360 335
Business Segments | Storage and other revenue | Gas Distribution and Storage        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 147 152 302 309
Business Segments | Storage and other revenue | Renewable Power Generation        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
Business Segments | Gas distribution sales | Liquids Pipelines        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
Business Segments | Gas distribution sales | Gas Transmission        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
Business Segments | Gas distribution sales | Gas Distribution and Storage        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 1,830 1,735 5,943 5,401
Business Segments | Gas distribution sales | Renewable Power Generation        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
Business Segments | Electricity revenue | Liquids Pipelines        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
Business Segments | Electricity revenue | Gas Transmission        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
Business Segments | Electricity revenue | Gas Distribution and Storage        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
Business Segments | Electricity revenue | Renewable Power Generation        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 77 52 154 94
Business Segments | Commodity sales | Liquids Pipelines        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
Revenue not from contract with customers 22,361 7,787 34,900 16,721
Business Segments | Commodity sales | Gas Transmission        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 36 28 74 52
Revenue not from contract with customers 44 29 93 66
Business Segments | Commodity sales | Gas Distribution and Storage        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 8 0 15 0
Revenue not from contract with customers 0 0 0 0
Business Segments | Commodity sales | Renewable Power Generation        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
Revenue not from contract with customers 0 0 0 0
Business Segments | Other Revenue | Liquids Pipelines        
Disaggregation of Revenue [Line Items]        
Revenue not from contract with customers 74 80 140 157
Business Segments | Other Revenue | Gas Transmission        
Disaggregation of Revenue [Line Items]        
Revenue not from contract with customers 0 32 30 25
Business Segments | Other Revenue | Gas Distribution and Storage        
Disaggregation of Revenue [Line Items]        
Revenue not from contract with customers 24 67 76 120
Business Segments | Other Revenue | Renewable Power Generation        
Disaggregation of Revenue [Line Items]        
Revenue not from contract with customers 87 90 181 167
Eliminations and Other        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
Total revenue 132 274 664 801
Eliminations and Other | Transportation revenue        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
Eliminations and Other | Storage and other revenue        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
Eliminations and Other | Gas distribution sales        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
Eliminations and Other | Electricity revenue        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
Eliminations and Other | Commodity sales        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
Revenue not from contract with customers 136 280 695 834
Eliminations and Other | Other Revenue        
Disaggregation of Revenue [Line Items]        
Revenue not from contract with customers 0 0 0 0
Intersegment revenue        
Disaggregation of Revenue [Line Items]        
Revenue not from contract with customers (4) (6) (31) (33)
Intersegment revenue | Liquids Pipelines        
Disaggregation of Revenue [Line Items]        
Revenue not from contract with customers 0 0 0 0
Intersegment revenue | Gas Transmission        
Disaggregation of Revenue [Line Items]        
Revenue not from contract with customers 5 4 11 12
Intersegment revenue | Gas Distribution and Storage        
Disaggregation of Revenue [Line Items]        
Revenue not from contract with customers (1) (1) 17 17
Intersegment revenue | Renewable Power Generation        
Disaggregation of Revenue [Line Items]        
Revenue not from contract with customers $ 0 $ 3 $ 3 $ 4