Commitments and Contingencies - Gross Future Minimum Transportation Demand and Firm Processing Charges (Detail) $ in Thousands	Sep. 30, 2019 USD ($)
Commitments and Contingencies Disclosure [Abstract]
2019	$ 4,544
2020	23,300
2021	19,797
2022	13,064
2023	14,600
Thereafter	19,440
Total	$ 94,745

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 Five Years

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

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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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