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v3.23.2

Revenue Recognition - Revenue by Product Type and Market (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2023 | Jun. 30, 2022 | Jun. 30, 2023 | Jun. 30, 2022
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues | $ 1,268.8 | $ 1,321.9 | $ 2,632.8 | $ 2,013.3
Other Income | 3.8 | 3.4 | 25.6 | 5.6
Designated as Hedging Instrument |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax | 29.3 | (31.4) | 128.5 | (318.3)
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net | (19.3) | (122.9) | (55.5) | (192.6)
Derivative, Gain (Loss) on Derivative, Net | 10.0 | (154.3) | 73.0 | (510.9)
Derivative contracts related to forecasted sales | Designated as Hedging Instrument |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax | 40.3 | (24.5) | 159.0 | (325.5)
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net | (30.3) | (122.6) | (80.9) | (190.6)
Derivative, Gain (Loss) on Derivative, Net | 10.0 | (147.1) | 78.1 | (516.1)
Financial trading contracts | Designated as Hedging Instrument |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax | (13.8) | (0.6) | (31.1) | 10.2
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net | 13.9 | 0.9 | 31.2 | 0.2
Derivative, Gain (Loss) on Derivative, Net | 0.1 | 0.3 | 0.1 | 10.4
Coal Contract and Physical commodity purchase / sale contracts | Designated as Hedging Instrument |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax | 40.3 | (24.5) | 159.0 | (325.5)
Thermal coal |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues | 857.4 | 808.4 | 1,756.6 | 1,510.7
Metallurgical coal |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues | 371.6 | 533.3 | 658.8 | 851.3
Other (2) |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues | 39.8 | (19.8) | 217.4 | (348.7)
Domestic | Thermal coal |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues | 489.9 | 492.5 | 1,080.3 | 984.3
Export | Thermal coal |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues | 367.5 | 315.9 | 676.3 | 526.4
Export | Metallurgical coal |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues | 371.6 | 533.3 | 658.8 | 851.3
Seaborne Thermal |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues | 399.5 | 354.9 | 746.0 | 606.1
Seaborne Thermal | Thermal coal |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues | 399.4 | 354.7 | 745.7 | 605.6
Seaborne Thermal | Metallurgical coal |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues | 0.0 | 0.0 | 0.0 | 0.0
Seaborne Thermal | Other (2) |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues | 0.1 | 0.2 | 0.3 | 0.5
Seaborne Thermal | Domestic | Thermal coal |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues | 31.9 | 39.8 | 69.4 | 80.2
Seaborne Thermal | Export | Thermal coal |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues | 367.5 | 314.9 | 676.3 | 525.4
Seaborne Thermal | Export | Metallurgical coal |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues | 0.0 | 0.0 | 0.0 | 0.0
Seaborne Metallurgical |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues | 372.5 | 533.8 | 660.9 | 855.1
Seaborne Metallurgical | Thermal coal |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues | 0.0 | 0.0 | 0.0 | 0.0
Seaborne Metallurgical | Metallurgical coal |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues | 371.6 | 533.3 | 658.8 | 851.3
Seaborne Metallurgical | Other (2) |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues | 0.9 | 0.5 | 2.1 | 3.8
Seaborne Metallurgical | Domestic | Thermal coal |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues | 0.0 | 0.0 | 0.0 | 0.0
Seaborne Metallurgical | Export | Thermal coal |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues | 0.0 | 0.0 | 0.0 | 0.0
Seaborne Metallurgical | Export | Metallurgical coal |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues | 371.6 | 533.3 | 658.8 | 851.3
Powder River Basin |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues | 259.7 | 229.7 | 565.0 | 480.9
Powder River Basin | Thermal coal |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues | 259.8 | 229.9 | 564.8 | 481.4
Powder River Basin | Metallurgical coal |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues | 0.0 | 0.0 | 0.0 | 0.0
Powder River Basin | Other (2) |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues | (0.1) | (0.2) | 0.2 | (0.5)
Powder River Basin | Domestic | Thermal coal |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues | 259.8 | 229.9 | 564.8 | 481.4
Powder River Basin | Export | Thermal coal |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues | 0.0 | 0.0 | 0.0 | 0.0
Powder River Basin | Export | Metallurgical coal |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues | 0.0 | 0.0 | 0.0 | 0.0
Other U.S. Thermal |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues | 199.9 | 224.9 | 449.3 | 428.0
Other U.S. Thermal | Thermal coal |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues | 198.2 | 223.8 | 446.1 | 423.7
Other U.S. Thermal | Metallurgical coal |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues | 0.0 | 0.0 | 0.0 | 0.0
Other U.S. Thermal | Other (2) |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues | 1.7 | 1.1 | 3.2 | 4.3
Other U.S. Thermal | Domestic | Thermal coal |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues | 198.2 | 222.8 | 446.1 | 422.7
Other U.S. Thermal | Export | Thermal coal |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues | 0.0 | 1.0 | 0.0 | 1.0
Other U.S. Thermal | Export | Metallurgical coal |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues | 0.0 | 0.0 | 0.0 | 0.0
Corporate and Other (1) |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues | 37.2 | (21.4) | 211.6 | (356.8)
Corporate and Other (1) | Thermal coal |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues | 0.0 | 0.0 | 0.0 | 0.0
Corporate and Other (1) | Trading and Brokerage Coal Deliveries |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues | 23.3 | 122.0 | 107.8 | 143.3
Corporate and Other (1) | Metallurgical coal |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues | 0.0 | 0.0 | 0.0 | 0.0
Corporate and Other (1) | Other (2) |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues | 37.2 | (21.4) | 211.6 | (356.8)
Corporate and Other (1) | Domestic | Thermal coal |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues | 0.0 | 0.0 | 0.0 | 0.0
Corporate and Other (1) | Export | Thermal coal |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues | 0.0 | 0.0 | 0.0 | 0.0
Corporate and Other (1) | Export | Metallurgical coal |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues | $ 0.0 | $ 0.0 | $ 0.0 | $ 0.0

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