Business Acquisition, Price of Acquired Entity

No definition available.

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- Definition

Finite Lived Intangible Liabilities

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- Definition

The capitalized costs incurred during the period (excluded from amortization) to purchase, lease or otherwise acquire an unproved property, including costs of lease bonuses and options to purchase or lease properties, the portion of costs applicable to minerals when land including mineral rights is purchased in fee, brokers' fees, recording fees, legal costs, and other costs incurred in acquiring properties.

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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.

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- Definition

The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

+ References

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- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Acquisition of Shoal Creek Mine Textuals (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended									9 Months Ended	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Apr. 01, 2017	Dec. 31, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 03, 2018
Business Combination, Separately Recognized Transactions [Line Items]
Depreciation, Depletion and Amortization										$ 119.9	$ 521.6	$ 601.0	$ 679.0
Contract Based Intangible Liabilities	$ 20.3	$ 8.4				$ 20.3						8.4	20.3
Revenues		1,117.4	$ 1,106.4	$ 1,149.0	$ 1,250.6	1,397.1	$ 1,412.6	$ 1,309.4	$ 1,462.7	1,326.2	4,252.6	4,623.4	5,581.8
Net income		(289.8)	$ (82.8)	37.1	124.2	252.6	$ 71.5	$ 113.7	$ 106.6	$ (216.5)	$ 498.6	(211.3)	544.4
Shoal Creek
Business Combination, Separately Recognized Transactions [Line Items]
Business Acquisition, Price of Acquired Entity		$ 389.8										$ 389.8		$ 389.8
Depreciation, Depletion and Amortization				$ 0.4	$ 0.5	$ 0.4
Revenues	12.8
Net income	$ 0.1
Excluded Acquisition Costs													$ 7.4