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Borrowing base.

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Line of credit facility covenant, minimum required asset coverage ratio on achievement of investment grade .

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Line of credit facility covenant, minimum required consolidated net leverage ratio after fiscal year.

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Line of credit facility covenant, minimum required consolidated net leverage ratio on current fiscal year.

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Line of credit facility covenant, minimum required current ratio.

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Line of credit facility covenant, minimum required interest coverage ratio ..

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

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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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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Identification of whether the entity has been in compliance with any credit facility debt covenants during the period.

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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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Debt and Other Long Term Obligations - Ultra Resources, Inc. - Credit Agreement - Additional Information (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Apr. 12, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Long-term debt, gross	$ 2,195,000		$ 3,759,000
RBL Credit Agreement
Debt Instrument [Line Items]
Long-term debt, gross	20,000
Ultra Resources, Inc.
Debt Instrument [Line Items]
Long-term debt, gross			$ 1,460,000
Ultra Resources, Inc. \| RBL Credit Agreement
Debt Instrument [Line Items]
Credit facility, current borrowing capacity	425,000	$ 400,000
Long-term debt, gross	20,000
Ultra Resources, Inc. \| RBL Credit Agreement \| Bank Of Montreal
Debt Instrument [Line Items]
Borrowing Base	1,400,000	$ 1,200,000
Ultra Resources, Inc. \| RBL Credit Agreement \| Bank Of Montreal \| Letters of Credit
Debt Instrument [Line Items]
Amount of commitments available for the issuance of letters of credit	$ 50,000
Ultra Resources, Inc. \| RBL Credit Agreement \| Bank Of Montreal \| Revolving Credit Facility
Debt Instrument [Line Items]
Minimum required interest coverage ratio, as percentage	250.00%
Minimum required current ratio, as percentage	100.00%
Minimum required consolidated net leverage ratio, as percentage on or before December 31, 2017	425.00%
Minimum required consolidated net leverage ratio, as percentage after December 31, 2017	400.00%
Minimum required asset coverage ratio, as percentage on achievement of investment grade	150.00%
Line of credit facility, covenant compliance	Ultra Resources was in compliance with all of its debt covenants under the RBL Credit Agreement
Ultra Resources, Inc. \| RBL Credit Agreement \| Bank Of Montreal \| Revolving Credit Facility \| LIBOR \| Minimum
Debt Instrument [Line Items]
Variable rate	2.50%
Ultra Resources, Inc. \| RBL Credit Agreement \| Bank Of Montreal \| Revolving Credit Facility \| LIBOR \| Maximum
Debt Instrument [Line Items]
Variable rate	3.50%
Ultra Resources, Inc. \| RBL Credit Agreement \| Bank Of Montreal \| Revolving Credit Facility \| Base Rate \| Minimum
Debt Instrument [Line Items]
Variable rate	1.50%
Ultra Resources, Inc. \| RBL Credit Agreement \| Bank Of Montreal \| Revolving Credit Facility \| Base Rate \| Maximum
Debt Instrument [Line Items]
Variable rate	2.50%