Revenue From Contracts With Customers - Narrative (Details) - USD ($)	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024
Coal Revenue
Disaggregation of Revenue [Line Items]
Capitalized contract cost, net	$ 0		$ 0
Capitalized contract cost, amortization	0	$ 0
Contract with customer, liability, revenue recognized	0
Third-Party Terminal Revenue
Disaggregation of Revenue [Line Items]
Capitalized contract cost, net	0		$ 0
Capitalized contract cost, amortization	0	$ 0
Contract with customer, liability, revenue recognized	$ 0

Amount of amortization expense for asset recognized from cost incurred to obtain or fulfill contract with customer.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 340
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
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Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer.

+ References

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Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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