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Summary of Significant Accounting Policies - New Accounting Pronouncements (Details) - Predecessor $ in Millions	3 Months Ended
	Mar. 31, 2017 USD ($)
Business Acquisition [Line Items]
Decrease in fair value of mineral interests	$ 3.5
Decrease to additional paid in capital	$ 3.5

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- Definition

Adjustments to Additional Paid in Capital, Purchase Accounting Adjustments

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- Definition

Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Mineral Interests

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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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