v3.25.4
FAIR VALUE OF FINANCIAL INSTRUMENTS AND RISK MANAGEMENT (Tables)
 12 Months Ended
Dec. 31, 2025
Fair Value Disclosures [Abstract]  
Summary of Fair Values and Carrying Values of Long-Term Debt
The carrying values and fair values of the Company’s long-term debt as at December 31, 2025 and 2024 are as follows:
2025202520242024
As at December 31 (millions of dollars)
Carrying ValueFair ValueCarrying ValueFair Value
Long-term debt, including current portion19,017 18,721 17,479 17,364 
Summary of Fair Value Hierarchy of Financial Assets and Liabilities
The fair value hierarchy of financial assets and liabilities as at December 31, 2025 and 2024 is as follows:
As at December 31, 2025 (millions of dollars)
Carrying
Value		Fair
 Value
Level 1
Level 2
Level 3
Liabilities:
    Long-term debt, including current portion19,017 18,721 — 18,721 — 
   Derivative instruments (Note 13)
Cash flow hedges, including current portion4 4 — 4 — 
19,021 18,725 — 18,725 — 

As at December 31, 2024 (millions of dollars)
Carrying
Value		Fair
 Value
Level 1
Level 2
Level 3
Liabilities:
    Long-term debt, including current portion
17,479 17,364 — 17,364 — 
   Derivative instruments (Notes 13 & 14)
Cash flow hedges, including current portion7 7 — 7 — 
17,486 17,371 — 17,371 — 
Summary of the Amounts Recorded in OCL and Reclassified to Financing Charges The following table shows the amounts recorded in OCI/OCL and reclassified to financing charges for the years ended December 31, 2025 and 2024:
Year ended December 31 (millions of dollars)
20252024
Amounts recorded in OCI/OCL
    Before tax loss21
    After tax loss11
Amounts reclassified to financing charges
    Before tax loss (gain)4 (4)
    After tax loss (gain)3 (3)