Derivative Instruments - Additional Information (Detail) $ in Thousands	9 Months Ended
Sep. 30, 2020 USD ($) Customer	Dec. 31, 2019 USD ($)
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Derivative assets	$ 28,403	$ 26,835
Derivative Asset	53,033	$ 6,881
Interest Rate Swap
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Derivative assets	$ 6,200
Number of derivative counterparties \| Customer	4
Derivative, Notional Amount	$ 300,000
Derivative, Average Fixed Interest Rate	136.00%
Commodity contracts
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Number of derivative counterparties \| Customer	7
Derivative Asset	$ 30,900
Commodity contracts \| Crude Oil
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Third-party quoted forward prices	NYMEX WTI
Commodity contracts \| MEH [Domain]
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Third-party quoted forward prices	MEH
Commodity contracts \| Natural Gas [Member]
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Third-party quoted forward prices	NYMEX HH

Derivative Instruments and Hedging Activities Disclosure [Line Items]

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Number Of Derivative Counterparty

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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- Definition

Average fixed interest rate related to the group of interest rate derivatives.

+ References

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Nominal or face amount used to calculate payment on derivative.

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Reference to the index or unit of measurement for the underlying which establishes the pricing terms of the derivative instrument. For example, the basis on the underlying for a natural gas futures contract might be the NYMEX price per million British thermal units (MMBtu).

+ References

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