The max value (monetary amount) of the award theplaintiff seeks in the legal matter.

No definition available.

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- Definition

Reasonable Value of Oil Reserves

+ References

No definition available.

+ Details

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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.

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

TakeOrPayArrangementTerms

+ References

No definition available.

+ Details

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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

No definition available.

+ Details

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- Definition

Amount of loss contingency liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14326-108349

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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=77896938&loc=d3e25336-109308

+ Details

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Period Type:	instant

- Definition

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).

+ References

+ Details

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- Details

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- Details

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- Details

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- Details

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Commitments and Contingencies (Details) $ in Millions, $ in Millions	12 Months Ended	336 Months Ended
	Dec. 31, 2018 AUD ($)	Dec. 31, 2042	Dec. 31, 2018 USD ($)	Sep. 30, 2016 USD ($)
Successor
Long-term Purchase Commitment [Line Items]
Take-or-pay obligations			$ 1,300.0
Take-or-pay Obligations Due In One Year			148.2
Successor \| Capital Additions
Long-term Purchase Commitment [Line Items]
Purchase commitments for capital expenditures			110.3
Unrecorded Unconditional Purchase Obligation, Due in Next Twelve Months			94.2
Successor \| Monto Coal Pty Limited
Long-term Purchase Commitment [Line Items]
LossContingencyDamagesSoughtValueMax	$ 1,100.0
Predecessor \| Berenergy
Long-term Purchase Commitment [Line Items]
Loss Contingency Accrual				$ 13.1
Reasonable Value of Oil Reserves			$ 1.0
Scenario, Forecast
Long-term Purchase Commitment [Line Items]
Take-or-pay Arrangement Terms Years (Maximum)		24