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Fair Value Measurements - Contingent Consideration (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2026 USD ($)	Jun. 30, 2025 USD ($)	Jun. 30, 2026 USD ($)	Jun. 30, 2025 USD ($)	Dec. 31, 2025
Changes in contingent consideration liability
Beginning balance	$ 16,995	$ 11,324	$ 18,000	$ 13,100
Noncash changes in fair value	$ 302	$ 2,005	$ (189)	$ 2,005
Fair Value, Liability, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Cost of Goods and Service, Excluding Depreciation, Depletion, and Amortization	Cost of Goods and Service, Excluding Depreciation, Depletion, and Amortization	Cost of Goods and Service, Excluding Depreciation, Depletion, and Amortization	Cost of Goods and Service, Excluding Depreciation, Depletion, and Amortization
Payments	$ (548)	$ (2,652)	$ (1,062)	$ (4,428)
Ending balance	$ 16,749	$ 10,677	$ 16,749	$ 10,677
Cost of Debt \| Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Contingent consideration, Measurement input	0.0546		0.0546		0.0546
Cost of Debt \| Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Contingent consideration, Measurement input	0.0835		0.0835		0.0835
Coal price volatility
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Contingent consideration, Measurement input	0.092		0.092		0.092
Market price of risk adjustment (annual)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Contingent consideration, Measurement input	0.067		0.067		0.067