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v3.25.3

Debt and Credit Facility - Summary of Interest Expense Relating to Senior Notes and Revolving Credit Facility (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Debt Instrument [Line Items] |  |  |  |  |  |
Total interest expense | $ 12.4 | $ 10.7 | [1],[2] | $ 36.1 | $ 33.3 | [1],[2]
Senior Notes and Revolving Credit Facility |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Interest expense on finance lease liabilities | 0.2 | 0.2 |  | 0.6 | 0.6 |
Interest expense capitalized as construction in progress | (0.9) | (2.5) |  | (3.7) | (6.3) |
Total interest expense | 12.4 | 10.7 |  | 36.1 | 33.3 |
Revolving Credit Facility |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Revolving Credit Facility interest expense, including commitment fees and finance cost amortization | 0.7 | 0.6 |  | 2.0 | 1.8 |
Senior Notes |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Senior Notes interest expense, including debt issuance cost amortization | $ 12.4 | $ 12.4 |  | $ 37.2 | $ 37.2 |
[1] | Adjusted to reflect the retrospective change in inventory valuation methodology from LIFO to WAC. See Note 14 for further discussion.
[2] | Adjusted to reflect the retrospective change in inventory valuation methodology from LIFO to WAC. See Note 14 for further discussion.

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