Coal Reserves, in tons

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[Line Items] for Other Commercial Events [Table]

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- Definition

Planned Divestiture, Agreed Upon Proceeds from Divestiture

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No definition available.

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- Definition

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=68055307&loc=d3e2420-110228

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-Publisher FASB
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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
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Gain (loss) related to the termination of a contract between the parties. The termination may be due to many causes including early termination of a lease by a lessee, a breach of contract by one party, or a failure to perform.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)(1)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 45
-Paragraph 28
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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- Definition

Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 360
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-Section 45
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-URI http://asc.fasb.org/extlink&oid=68055307&loc=d3e2443-110228

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- Definition

The cash inflow from the sale of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Other Events (Details) T in Millions, $ in Millions, $ in Millions		1 Months Ended	3 Months Ended					6 Months Ended		12 Months Ended
	Apr. 01, 2017 USD ($)	Jun. 30, 2018 AUD ($) T	Sep. 30, 2018 USD ($)	Sep. 30, 2018 AUD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	Apr. 01, 2017 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2018 AUD ($)	Sep. 30, 2019 AUD ($)	Feb. 06, 2018	Mar. 31, 2017	Nov. 30, 2016 USD ($)	Nov. 30, 2015 USD ($)
Successor
Other Commercial Events [Line Items]
Proceeds from disposal of assets, net of notes receivable						$ 2.5		$ 52.6
Net gain on disposal of assets					$ (1.6)	0.5		29.0
Asset Impairment Charges					0.0	0.0		0.0
Successor \| Contract Termination [Member]
Other Commercial Events [Line Items]
Asset Impairment Charges					$ 0.0			0.0
Successor \| Red Mountain Joint Venture
Other Commercial Events [Line Items]
Proceeds from disposal of assets, net of notes receivable								20.0
Net gain on disposal of assets								7.1
Successor \| Queensland’s Bowen Basin [Member]
Other Commercial Events [Line Items]
Proceeds from disposal of assets, net of notes receivable									$ 37.0
Net gain on disposal of assets								$ 20.6
Successor \| DTA and PBGC
Other Commercial Events [Line Items]
Equity method investment, ownership percentage											50.00%
Predecessor
Other Commercial Events [Line Items]
Proceeds from disposal of assets, net of notes receivable							$ 24.3
Net gain on disposal of assets	$ 0.0						22.8
Asset Impairment Charges	$ 0.0						30.5
Predecessor \| Contract Termination [Member]
Other Commercial Events [Line Items]
Asset Impairment Charges							30.5
Predecessor \| DTA and PBGC
Other Commercial Events [Line Items]
Equity method investment, ownership percentage												37.50%
Proceeds from disposal of assets, net of notes receivable						20.5
Net gain on disposal of assets						19.7	$ 19.7
Predecessor \| Metropolitan Collieries Pty Ltd [Member]
Other Commercial Events [Line Items]
Planned Divestiture, Agreed Upon Proceeds from Divestiture													$ 200.0
Stanmore Coal Limited [Member] \| Successor
Other Commercial Events [Line Items]
Coal Reserves, in tons \| T		23
Proceeds from disposal of assets, net of notes receivable		$ 30.0
Stanmore Coal Limited [Member] \| Scenario, Forecast
Other Commercial Events [Line Items]
Proceeds from disposal of assets, net of notes receivable				$ 6.0						$ 24.0
Net gain on disposal of assets			$ 22.0
Bowie Resource Partners, LLC [Member] \| Successor \| New Mexico And Colorado Assets [Member]
Other Commercial Events [Line Items]
Gain (Loss) on Contract Termination						$ 20.0
Bowie Resource Partners, LLC [Member] \| Predecessor \| New Mexico And Colorado Assets [Member]
Other Commercial Events [Line Items]
Planned Divestiture, Agreed Upon Proceeds from Divestiture														$ 358.0