Commitments and Contingencies - Gross Future Minimum Transportation Demand and Firm Processing Charges (Detail) $ in Thousands	Dec. 31, 2018 USD ($)
Commitments and Contingencies Disclosure [Abstract]
2019	$ 18,485
2020	18,691
2021	10,903
Thereafter	0
Total	$ 48,079

Transportation Demand and Firm Processing Charges, Gross Future Minimum Payments

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Transportation Demand And Firm Processing Charges Gross Future Minimum Payments In One Year

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Transportation Demand and Firm Processing Charges, Gross Future Minimum Payments, in Three Years

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Transportation Demand and Firm Processing Charges, Gross Future Minimum Payments, in Two Years

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Transportation Demand and Firm Processing Charges, Gross Future Minimum Payments, Thereafter

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