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[Axis] Credit Facility Amendment Deductible amount Deductible amount Deductible amount Seaborne Mining Seaborne Mining [Member] Seaborne Mining Property, Plant and Equipment, Type [Axis] Long-Lived Asset, Class [Axis] Stock Price or TSR Estimation Method Stock Price or TSR Estimation Method [Text Block] Entity Tax Identification Number Entity Tax Identification Number Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation, Beginning Balance Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation, Ending Balance Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation Changes in accrued expenses related to capital expenditures Increase (Decease) in Accrued Liabilities Related to Capital Expenditures, Investing Activities Increase (Decease) in Accrued Liabilities Related to Capital Expenditures, Investing Activities At-risk assets At-risk assets At-risk assets Entity 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Name Measure Name Income Tax Disclosure [Text Block] Income Tax Disclosure [Text Block] R3 Renewables R3 Renewables [Member] R3 Renewables Pay vs Performance Disclosure [Line Items] Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Debt Instrument [Line Items] Debt Instrument [Line Items] Other current assets Increase (Decrease) in Other Current Assets Pay vs Performance Disclosure Pay vs Performance Disclosure [Table] Corporate and Other (1) Corporate Segment and Other Operating Segment [Member] Retirement Plan Type [Domain] Retirement Plan Type [Domain] Additional paid-in capital Additional Paid-in Capital [Member] Entity Filer Category Entity Filer Category Additions to property, plant, equipment and mine development Increase (Decrease) in Property, Plant and Equipment, Investing Activities Increase (Decrease) in Property, Plant and Equipment, Investing Activities Additions to property, plant, equipment and mine development excluding corporate and other 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