Number of Buyers

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- Definition

Patriot Federal Black Lung, Gain (Loss) Due to Settlement

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Patriot Federal Black Lung, Payment for Settlement

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- Definition

Amount of loss contingency liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 450
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483076/450-20-50-1

Reference 2: http://www.xbrl.org/2003/role/recommendedDisclosureRef
-Topic 450
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483076/450-20-50-10

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Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 440
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482648/440-10-50-4

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Amount of the unrecorded obligation to transfer funds in the future for fixed or minimum amounts or quantities of goods or services at fixed or minimum prices (for example, as in take-or-pay contracts or throughput contracts).

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Commitments and Contingencies (Details) $ in Millions	Sep. 30, 2023 USD ($)	Aug. 08, 2023 USD ($)	Dec. 31, 2022 USD ($)	Oct. 09, 2015 buyer	Dec. 31, 2007 USD ($)
Long-term Purchase Commitment [Line Items]
Patriot Black Lung, Payment for Settlement		$ 72.0
Patriot Federal Black Lung, Gain (Loss) Due to Settlement		3.9
Patriot Federal Black Lung, Settlement Fees		$ 4.2
Patriot
Long-term Purchase Commitment [Line Items]
Number of buyers \| buyer				2
Black Lung Occupational Disease Liability \| Patriot \| Spinoff
Long-term Purchase Commitment [Line Items]
Initially determined potential exposure from patriot bankruptcy					$ 150.0
Black Lung Occupational Disease Liability \| Patriot \| Disposal Group, Disposed of by Means Other than Sale, Not Discontinued Operations
Long-term Purchase Commitment [Line Items]
Initially determined potential exposure from patriot bankruptcy			$ 82.3
Capital Addition Purchase Commitments
Long-term Purchase Commitment [Line Items]
Unrecorded unconditional purchase obligation (within next five years)	$ 91.1
Unrecorded unconditional purchase obligation (within next 12 months)	$ 84.7