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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Related Party Transactions - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
LM4
Related Party Transaction [Line Items]
Percentage of ownership in joint venture	50.00%		50.00%
Credit Concentration Risk \| Revenue
Related Party Transaction [Line Items]
Revenues attributable to fee based commercial agreements	100.00%	100.00%	100.00%	100.00%
Hess
Related Party Transaction [Line Items]
Minimum volume shortfall fee payments	$ 7.8	$ 3.0	$ 11.9	$ 6.5
Hess \| Credit Concentration Risk \| Revenue
Related Party Transaction [Line Items]
Revenues attributable to fee based commercial agreements	100.00%	100.00%	100.00%	100.00%
Targa Resources Corp. \| LM4
Related Party Transaction [Line Items]
Percentage of ownership in joint venture	50.00%		50.00%