Asset Acquisition, Consideration Transferred

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Asset Acquisition, Consideration Transferred, Equity Interests Issued and Issuable

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Asset Acquisition, Equity Interest Issued or Issuable, Number of Shares

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Asset Acquisition, Provisional Information, Initial Accounting Incomplete, Adjustment, Consideration Transferred

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Asset Acquisition, Share Price

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Debt Instrument, Collateral as Percentage Proved Reserves

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Debt Instrument, Covenant Compliance, Current Ratio

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Debt Instrument, Covenant Compliance, Debt To EBITDAX Ratio

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Net mineral acres acquired is the sum of the fractional interest purchased during the period based on working interests or other economic arrangements.

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Long-term Debt, Period between Maturity Dates

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Number of Proved Developed Nonproducing Wells Acquired, Net

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Number of Proved Developed Producing Wells Acquired, Net

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Amount of liability recognized arising from contingent consideration in a business combination.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Period between issuance and maturity of long-term debt, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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The cash outflow to purchase of mineral interests in oil and gas properties for use in the normal oil and gas operations and not intended for resale.

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The cash outflow to repay long-term debt that is not secured by collateral. Excludes repayments of tax exempt unsecured debt.

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Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

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SUBSEQUENT EVENTS (Details)						1 Months Ended		9 Months Ended
SUBSEQUENT EVENTS (Details)	Nov. 09, 2018 USD ($)	Oct. 11, 2018 USD ($)	Oct. 05, 2018 USD ($)	Oct. 01, 2018 USD ($) well a $ / shares shares	May 15, 2018	Nov. 09, 2018 USD ($)	Nov. 09, 2018 shares	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	May 13, 2013
Subsequent Event [Line Items]
Cash consideration								$ 125,487,059	$ 11,039,824
Interest rate (percent)								8.00%
Senior Second Lien Notes Due 2023 \| Second Lien Notes
Subsequent Event [Line Items]
Interest rate (percent)					8.50%
Debt instrument, basis spread on variable rate (percent)					3.00%
Covenant compliance, debt to EBITDAX ratio					3.0
The 2013 Follow-on Notes \| Senior Unsecured Notes
Subsequent Event [Line Items]
Interest rate (percent)										8.00%
Subsequent Event \| Revolving Credit Facility
Subsequent Event [Line Items]
Revolving credit facility, maximum borrowing			$ 750,000,000.0
Debt term			5 years
Period between maturity dates			91 days
Current borrowing capacity			$ 425,000,000
Covenant compliance, debt to EBITDAX ratio			4.00
Covenant compliance, current ratio			1.00
Percentage of proven reserves where mortgages secured (percent)			85.00%
Subsequent Event \| Revolving Credit Facility \| Federal funds effective rate
Subsequent Event [Line Items]
Debt instrument, basis spread on variable rate (percent)			0.50%
Subsequent Event \| Revolving Credit Facility \| LIBOR
Subsequent Event [Line Items]
Debt instrument, basis spread on variable rate (percent)			1.00%
Subsequent Event \| Revolving Credit Facility \| LIBOR \| Minimum
Subsequent Event [Line Items]
Debt instrument, basis spread on variable rate (percent)			1.75%
Subsequent Event \| Revolving Credit Facility \| LIBOR \| Maximum
Subsequent Event [Line Items]
Debt instrument, basis spread on variable rate (percent)			2.75%
Subsequent Event \| Revolving Credit Facility \| Base rate \| Minimum
Subsequent Event [Line Items]
Debt instrument, basis spread on variable rate (percent)			0.75%
Subsequent Event \| Revolving Credit Facility \| Base rate \| Maximum
Subsequent Event [Line Items]
Debt instrument, basis spread on variable rate (percent)			1.75%
Subsequent Event \| Additional Second Lien Notes \| Senior Secured Second Lien Notes
Subsequent Event [Line Items]
Debt issued			$ 350,000,000.0
Subsequent Event \| The 2013 Follow-on Notes
Subsequent Event [Line Items]
Repayments of senior unsecured debt		$ 102,800,000
Subsequent Event \| W Energy
Subsequent Event [Line Items]
Number of net PDP wells acquired (wells) \| well				27.2
Number of net PDNP wells acquired (wells) \| well				5.9
Mineral acres acquired, net (in acres) \| a				10,633
Adjustment to consideration transferred				$ 2,200,000		$ 17,000,000
Cash consideration	$ 97,800,000			117,100,000
Total fair value of consideration transferred				$ 341,600,000
Number of shares issued (shares) \| shares				51,476,961			7,564,875
Issuance of common stock				$ 220,800,000
Share price (dollars per share) \| $ / shares				$ 4.29
Contingent consideration				$ 23,000,000