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Stock-Based Compensation Plans - Directors' DSU Plan (Details) - Director - DSUs shares in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2024 shares | Dec. 31, 2023 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Unit with underlying value equivalent to common shares | 1 |
Number of units (thousands) |  |
DSUs outstanding, beginning of year (shares) | 241 | 224
Granted (shares) | 29 | 40
Notional dividends reinvested (shares) | 10 | 10
Paid out (shares) | (39) | (33)
DSUs outstanding, end of year (shares) | 241 | 241

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