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Line of credit facility covenant, maximum required consolidated net leverage ratio.

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Line of credit facility covenant maximum required consolidated net leverage ratio on rolling period four and thereafter.

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Line of credit facility covenant, maximum required consolidated net leverage ratio on rolling period one.

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Line of credit facility covenant, maximum required consolidated net leverage ratio on rolling period three.

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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 end of fiscal period.

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Line of credit facility covenant, minimum required consolidated net leverage ratio, incremental interest rate.

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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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Line of credit facility covenant, rolling period one, minimum required hedging percentage.

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Percentage of collateral coverage.

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Scheduled borrowing base redeterminations date.

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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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Long Term Debt - Ultra Resources, Inc. - Credit Agreement - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Feb. 14, 2019	Dec. 31, 2018	Nov. 30, 2018
Debt Instrument [Line Items]
Long-term debt, gross	$ 1,963,656		$ 2,044,035
Ultra Resources, Inc. \| Credit Agreement
Debt Instrument [Line Items]
Credit facility, current borrowing capacity	325,000	$ 325,000
Long-term debt, gross	38,000
Ultra Resources, Inc. \| Credit Agreement \| Bank Of Montreal
Debt Instrument [Line Items]
Borrowing Base		1,300,000
Ultra Resources, Inc. \| 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. \| Credit Agreement \| Bank Of Montreal \| Revolving Credit Facility
Debt Instrument [Line Items]
Interest rate description	The Revolving Credit Facility bears interest either at a rate equal to (a) a customary London interbank offered rate plus an applicable margin that varies from 250 to 350 basis points or (b) the base rate plus an applicable margin that varies from 150 to 250 basis points. If borrowings are outstanding during a period that the Company’s consolidated net leverage ratio exceeds 4.00 to 1.00 at the end of any fiscal quarter as described below, the interest rate on such borrowings shall be at a per annum rate that is 0.25% higher than the rate that would otherwise apply until the Company has provided financial statements indicating that the consolidated net leverage ratio no longer exceeds 4.00 to 1.00.
Minimum required consolidated net leverage ratio, as percentage	400.00%
Interest rate on minimum required consolidated net leverage ratio exceeds 4.00 to 1.00	0.25%
Maximum required consolidated net leverage ratio, as percentage	400.00%
Maturity date	Jan. 12, 2022
Ultra Resources, Inc. \| Credit Agreement \| Bank Of Montreal \| Revolving Credit Facility \| LIBOR \| Minimum
Debt Instrument [Line Items]
Variable rate	2.50%
Ultra Resources, Inc. \| Credit Agreement \| Bank Of Montreal \| Revolving Credit Facility \| LIBOR \| Maximum
Debt Instrument [Line Items]
Variable rate	3.50%
Ultra Resources, Inc. \| Credit Agreement \| Bank Of Montreal \| Revolving Credit Facility \| Base Rate \| Minimum
Debt Instrument [Line Items]
Variable rate	1.50%
Ultra Resources, Inc. \| Credit Agreement \| Bank Of Montreal \| Revolving Credit Facility \| Base Rate \| Maximum
Debt Instrument [Line Items]
Variable rate	2.50%
Ultra Resources, Inc. \| Credit Agreement \| Barclays Bank PLC
Debt Instrument [Line Items]
Long-term debt, gross		975,000
Ultra Resources, Inc. \| Third Amendment
Debt Instrument [Line Items]
Percentage of collateral coverage			95.00%	85.00%
Ultra Resources, Inc. \| Credit Agreement Fourth Amendment \| Bank Of Montreal
Debt Instrument [Line Items]
Borrowing Base		$ 1,300,000
Next scheduled borrowing base redeterminations date	Oct. 31, 2019
Ultra Resources, Inc. \| Credit Agreement Fourth Amendment \| 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 asset coverage ratio, as percentage on achievement of investment grade	150.00%
Maximum required consolidated net leverage ratio, as percentage, for each fiscal quarter ending during the period from March 31, 2019 through June 30, 2019	475.00%
Maximum required consolidated net leverage ratio, as percentage, for each fiscal quarter ending during the period from September 30, 2019 through June 30, 2020	490.00%
Maximum required consolidated net leverage ratio, as percentage, for fiscal quarter ending September 30, 2020	450.00%
Maximum required consolidated net leverage ratio, as percentage, the fiscal quarter ending December 31, 2020 and each other fiscal quarter end thereafter	425.00%
Consolidated net leverage ratio	411.00%
Consolidated interest coverage ratio	326.00%
Ultra Resources, Inc. \| Second Amendment \| Bank Of Montreal \| Revolving Credit Facility
Debt Instrument [Line Items]
Net leverage ratio through September 29, 2019, minimum required hedging percentage	65.00%
Net leverage ratio beginning on September 30, 2019 and ending on March 30, 2020, minimum required hedging percentage	50.00%
Ultra Resources, Inc. \| Second Amendment \| Bank Of Montreal \| Revolving Credit Facility \| Maximum
Debt Instrument [Line Items]
Net leverage ratio through September 29, 2019, minimum required hedging percentage	65.00%
Net leverage ratio beginning on September 30, 2019 and ending on March 30, 2020, minimum required hedging percentage	50.00%