SHARE CAPITAL AND WARRANTS - Treasury Shares (Details) - Treasury Shares - CAD ($) shares in Thousands, $ in Millions |
9 Months Ended | 12 Months Ended |
|---|---|---|
Sep. 30, 2026 |
Dec. 31, 2025 |
|
| Number of Common Shares | ||
| Outstanding, Beginning of Year (in shares) | 5,258 | 2,000 |
| Purchased Under Employee Benefit Plan (in shares) | 7,300 | 7,100 |
| Distributed Under Employee Benefit Plan (in shares) | (3,792) | (3,842) |
| Outstanding, End of Period (in shares) | 8,766 | 5,258 |
| Amount | ||
| Outstanding, Beginning of Year | $ 116 | $ 43 |
| Purchased Under Employee Benefit Plan | 284 | 155 |
| Distributed Under Employee Benefit Plan | (88) | (82) |
| Outstanding, End of Period | $ 312 | $ 116 |