Coal Trading Assets and Liabilities, Net, Fair Value Disclosure

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Coal Trading.

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Futures, Swaps And Options Fair Value Disclosure

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Physical Purchase Sale Contracts Fair Value Disclosure

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Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

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Amount of transfers of assets measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

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- Definition

Amount of unrealized (holding) gain (loss) which is included in the statement of income (or changes in net assets) related to those assets still held at the reporting date for which fair value is measured on a recurring basis using significant unobservable inputs (Level 3).

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of gain (loss) recognized in the income statement of financial instrument classified as a derivative asset (liability) after deduction of derivative liability (asset), measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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Amount of sales of financial instrument classified as a derivative asset (liability) after deduction of derivative liability (asset), measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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-Publisher FASB
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Amount of settlements of financial instrument classified as a derivative asset (liability) after deduction of derivative liability, measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of transfers of financial instrument classified as a derivative asset (liability) after deduction of derivative liability (asset) into level 3 of the fair value hierarchy.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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Amount of transfers of financial instrument classified as derivative asset (liability) after deduction of derivative liability (asset) out of level 3 of the fair value hierarchy.

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Fair value of financial instrument classified as derivative asset (liability) after deduction of derivative liability (asset), measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Coal Trading - Fair Value (Details) - Coal Trading - USD ($) $ in Millions	3 Months Ended			6 Months Ended
	Jun. 30, 2017	Apr. 01, 2017	Jun. 30, 2016	Jun. 30, 2016	Dec. 31, 2016	Jun. 30, 2015
Coal Trading (Textuals) [Abstract]
Fair value hierarchy transfers from Level 1 to Level 2	$ 0.0					$ 0.0
Fair value hierarchy transfers from Level 2 to Level 1	0.0					$ 0.0
Successor \| Fair Value, Measurements, Recurring
Fair value coal trading net assets (liabilities) measured on recurring basis:
Physical purchase/sale contracts	(0.6)
Total net financial assets (liabilities)	(0.6)
Successor \| Level 1 \| Fair Value, Measurements, Recurring
Fair value coal trading net assets (liabilities) measured on recurring basis:
Physical purchase/sale contracts	0.0
Total net financial assets (liabilities)	0.0
Successor \| Level 2 \| Fair Value, Measurements, Recurring
Fair value coal trading net assets (liabilities) measured on recurring basis:
Physical purchase/sale contracts	(0.6)
Total net financial assets (liabilities)	(0.6)
Successor \| Level 3
Changes in the Company's recurring Level 3 net financial assets
Beginning of period	(0.7)
Transfers into Level 3	0.0
Transfers out of Level 3	0.7
Included in earnings	0.0
Sales	0.0
Settlements	0.0
End of period	0.0	$ (0.7)
Changes in unrealized gains (losses)	0.0
Successor \| Level 3 \| Fair Value, Measurements, Recurring
Fair value coal trading net assets (liabilities) measured on recurring basis:
Physical purchase/sale contracts	0.0
Total net financial assets (liabilities)	0.0
Predecessor \| Fair Value, Measurements, Recurring
Fair value coal trading net assets (liabilities) measured on recurring basis:
Futures, swaps and options					$ (0.1)
Physical purchase/sale contracts					(0.4)
Total net financial assets (liabilities)					(0.5)
Predecessor \| Level 1 \| Fair Value, Measurements, Recurring
Fair value coal trading net assets (liabilities) measured on recurring basis:
Futures, swaps and options					0.0
Physical purchase/sale contracts					0.0
Total net financial assets (liabilities)					0.0
Predecessor \| Level 2 \| Fair Value, Measurements, Recurring
Fair value coal trading net assets (liabilities) measured on recurring basis:
Futures, swaps and options					(0.1)
Physical purchase/sale contracts					0.7
Total net financial assets (liabilities)					0.6
Predecessor \| Level 3
Changes in the Company's recurring Level 3 net financial assets
Beginning of period	$ (0.7)	(1.1)	$ (3.9)	$ (15.6)
Transfers into Level 3		0.0	0.4	0.4
Transfers out of Level 3		0.2	0.0	10.7
Included in earnings		0.2	(1.3)	(1.4)
Sales		0.0	0.0	(0.1)
Settlements		0.0	3.7	4.9
End of period		(0.7)	(1.1)	(1.1)
Changes in unrealized gains (losses)		$ 0.3	$ (0.1)	$ (0.2)
Predecessor \| Level 3 \| Fair Value, Measurements, Recurring
Fair value coal trading net assets (liabilities) measured on recurring basis:
Futures, swaps and options					0.0
Physical purchase/sale contracts					(1.1)
Total net financial assets (liabilities)					$ (1.1)