Long Term Debt - Ultra Resources, Inc. - Unsecured Notes - Additional Information (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Aggregate principal amounts outstanding	$ 1,985,758	$ 2,044,035
Ultra Resources, Inc. \| 6.875% Senior, Unsecured Notes Due 2022
Debt Instrument [Line Items]
Interest payment terms	The 2022 Notes will mature on April 15, 2022. Interest on the 2022 Notes accrue at an annual rate of 6.875% and interest payment dates for the 2022 Notes are April 15 and October 15 of each year.
Stated interest rate	6.875%
Ultra Resources, Inc. \| 6.875% Senior, Unsecured Notes Due 2022 \| Exchange Agreement
Debt Instrument [Line Items]
Aggregate principal amounts outstanding	$ 150,400
Ultra Resources, Inc. \| 7.125% Senior, Unsecured Notes Due 2025
Debt Instrument [Line Items]
Interest payment terms	The 2025 Notes will mature on April 15, 2025. Interest on the 2025 Notes accrue at an annual rate of 7.125% and interest payment dates for the 2025 Notes are April 15 and October 15 of each year. Interest will be paid on the Unsecured Notes from the issue date until maturity.
Stated interest rate	7.125%
Ultra Resources, Inc. \| 7.125% Senior, Unsecured Notes Due 2025 \| Exchange Agreement
Debt Instrument [Line Items]
Aggregate principal amounts outstanding	$ 225,000

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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