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v3.25.1

Long-term Debt - Narrative (Details) |  |  |  |  | 3 Months Ended |  |
--- | --- | --- | --- | --- | --- | --- | ---
Feb. 19, 2025 $ / shares | Nov. 25, 2024 USD ($) days | Jan. 18, 2024 USD ($) | Mar. 01, 2022 USD ($) $ / shares | Mar. 31, 2025 USD ($) $ / shares | Mar. 31, 2024 USD ($) $ / shares | Dec. 31, 2024 USD ($) | Mar. 31, 2023 USD ($)
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Interest expense, net of capitalized interest |  |  |  |  | $ 11,500,000 | $ 14,700,000 |  |
Finance lease obligations |  |  |  |  | 23,500,000 |  | $ 25,100,000 |
Interest Paid, Capitalized, Investing Activity |  |  |  |  | 9,900,000 | $ 11,500,000 |  |
2024 Credit Agreement Availability |  |  |  |  | $ 270,700,000 |  |  |
Dividends declared per share | $ / shares |  |  |  |  | $ 0.075 | $ 0.075 |  |
Interest Costs Capitalized |  |  |  |  | $ 2,200,000 | $ 0 |  |
Anglo American Acquisition |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Upfront cash payment for planned acquisition |  | $ 2,058,000,000.000 |  |  |  |  |  |
Payments to Acquire Businesses, Gross |  | 75,000,000 |  |  |  |  |  |
Letter of Credit |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Stated interest rate |  |  |  |  | 0.75% |  |  |
Line of credit facility, maximum borrowing capacity |  |  |  |  | $ 250,000,000 |  |  |
Debt instrument, fronting fee |  |  | 0.125% |  |  |  |  |
Letters of credit outstanding, amount |  |  |  |  | 49,300,000 |  |  |
Line of Credit Facility, Commitment Fee Percentage |  |  | 0.50% |  |  |  |  |
Revolving credit facility |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Debt issuance cost |  | $ 900,000 | $ 9,700,000 |  |  |  |  |
Line of credit facility, maximum borrowing capacity |  |  | $ 320,000,000 |  |  |  |  |
Maximum |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  | 3.25% |  |  |  |  |
Maximum | Letter of Credit |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  | 4.25% |  |  |  |  |
Maximum | Revolving credit facility |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  | 4.25% |  |  |  |  |
Minimum |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  | 2.50% |  |  |  |  |
Minimum | Letter of Credit |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  | 3.50% |  |  |  |  |
Minimum | Revolving credit facility |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  | 3.50% |  |  |  |  |
BUMA Loan Note |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Stated interest rate |  | 10.00% |  |  |  |  |  |
Proceeds from Notes Payable |  | $ 9,300,000 |  |  |  |  |  |
Interest Costs Capitalized |  |  |  |  | $ 200,000 |  |  |
Bridge Facility |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Basis spread on variable rate |  | 8.00% |  |  |  |  |  |
Line of credit facility, maximum borrowing capacity |  | $ 2,075,000,000.000 |  |  |  |  |  |
Debt Instrument, base rate plus applicable margin |  | 7.00% |  |  |  |  |  |
Debt Instrument, Number of Days Following Closing Date | days |  | 90 |  |  |  |  |  |
Debt Instrument, Term |  | 364 days |  |  |  |  |  |
Bridge Facility | Maximum |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Basis spread on variable rate |  | 0.75% |  |  |  |  |  |
Senior Notes | 3.250% Convertible Senior Notes due March 2028 (2028 Convertible Notes) |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Stated interest rate |  |  |  |  | 3.25% |  |  |
Long-term debt |  |  |  |  | $ 320,000,000.0 |  | $ 320,000,000.0 |
Principal amount |  |  |  | $ 320,000,000 |  |  |  |
Debt Issuance Costs, Gross |  |  |  |  |  |  |  | $ 11,200,000
Debt Conversion, Converted Instrument, Rate |  |  |  |  | 1.00% |  |  |
Debt Instrument, Convertible, Conversion Ratio |  |  |  | 50.3816 |  |  |  |
Debt Instrument, Convertible, Revised Conversion Ratio | 51.7762 |  |  |  |  |  |  |
Debt Instrument, Convertible, Conversion Price | $ / shares | $ 19.31 |  |  | $ 19.85 |  |  |  |
Debt Instrument, Principle Amount |  |  |  |  | $ 1,000 |  |  |

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