Amount of cost for defined contribution plan.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 70
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480794/715-70-50-1

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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- Definition

Percentage of entity's employees covered by collective-bargaining arrangement (CBA) to all entity's employees in multiemployer pension plan determined to be individually significant.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 715
-SubTopic 80
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480576/715-80-50-5

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Employee Benefit Plans (Details) - USD ($) $ in Millions	12 Months Ended
Employee Benefit Plans (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
UMWA Collective Bargaining Agreement
Defined Contribution Plan Disclosure [Line Items]
Proportion of company's employees represented by CBA (as a percent)	56.00%
Successor Benefit Plan
Defined Contribution Plan Disclosure [Line Items]
Contributions to defined contribution plans	$ 4.9	$ 4.0	$ 3.2