Related Party Transactions - Additional Information (Detail) - USD ($)	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Related Party Transaction [Line Items]
Earnings from equity investments	$ 2,700,000
LM4
Related Party Transaction [Line Items]
Percentage of ownership in joint venture	50.00%
Expenses incurred under gas processing agreement	$ 6,400,000	$ 0
Earnings from equity investments	$ 2,700,000	$ 0
Credit Concentration Risk \| Revenue
Related Party Transaction [Line Items]
Revenues attributable to fee based commercial agreements	100.00%	100.00%
Hess
Related Party Transaction [Line Items]
Minimum volume shortfall fee payments	$ 1,000,000.0	$ 2,800,000
Expenses incurred under gas processing agreement	$ 15,500,000	$ 10,600,000
Hess \| Credit Concentration Risk \| Revenue
Related Party Transaction [Line Items]
Revenues attributable to fee based commercial agreements	100.00%	100.00%
Targa Resources Corp. \| LM4
Related Party Transaction [Line Items]
Percentage of ownership in joint venture	50.00%

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Percentage of ownership In joint venture.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount of income (loss) for proportionate share of equity method investee's income (loss).

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Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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