Number of Buyers

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- Definition

Securities class action settlement

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- Definition

Take Or Pay Arrangement Term

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- Definition

Represents the estimated contractual cash spend in the next twelve months after the balance sheet date related to various short term take or pay arrangements in the U.S. and Australia associated with rail and port commitments for the delivery of coal including amounts relating to export facilities.

+ References

No definition available.

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Represents the total projected cash contractual obligation spend associated with various long and short term take or pay arrangements in the U.S. and Australia for rail and port commitments for the delivery of coal including amounts relating to export facilities.

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No definition available.

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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.

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- Definition

Amount of loss contingency liability.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
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Amount of increase (decrease) in loss contingency liability.

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123406679&loc=d3e25336-109308

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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	12 Months Ended
Commitments and Contingencies (Details) $ in Millions	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Jul. 29, 2022 USD ($)	Oct. 09, 2015 buyer	Dec. 31, 2007 USD ($)
Long-term Purchase Commitment [Line Items]
Take-or-pay arrangement term (up to)	20 years
Take-or-pay obligations	$ 1,400.0
Take or pay obligations due in one year	103.0
Securities class action settlement				$ 4.6
Patriot Coal Corporation
Long-term Purchase Commitment [Line Items]
Number of buyers \| buyer					2
Patriot Coal Corporation \| Disposal Group, Disposed of by Means Other than Sale, Not Discontinued Operations \| Black Lung Occupational Disease Liability
Long-term Purchase Commitment [Line Items]
Loss contingency accrual	82.3	$ 87.2				$ 150.0
Loss contingency accrual, mark-to-market adjustment	2.7	$ 2.1	$ 4.2
Capital Additions
Long-term Purchase Commitment [Line Items]
Unrecorded unconditional purchase obligation (within next five years)	102.1
Unrecorded unconditional purchase obligation (within next 12 months)	$ 94.1