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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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The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders.

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The percentage rate used to calculate dividend payments on preferred stock.

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No definition available.

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ACQUISITIONS AND DIVESTITURES-Pecos County Consideration (Details) - USD ($) $ / shares in Units, $ in Thousands				3 Months Ended		6 Months Ended
	Feb. 28, 2017	Jan. 24, 2017	Jan. 18, 2017	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Pro forma financial information
Net income (loss) available to common stockholders				$ (16,274)	$ (27,029)	$ (18,872)	$ 161,522
8% Convertible Preferred Stock
ACQUISITIONS AND DIVESTITURES
Dividend rate (as a percent)		8.00%	8.00%
Pecos County Assets
ACQUISITIONS AND DIVESTITURES
Purchase price	$ 699,200
Pro forma financial information
Revenue						263,637
Net income (loss)						216,553
Net income (loss) available to common stockholders						$ 168,546
Pro forma net income (loss) per share of common stock:
Basic (in dollars per share)						$ 1.43
Diluted (in dollars per share)						$ 1.43