Segments - Financial Data for Each Reportable Segment (Detail) - USD ($) $ in Millions	3 Months Ended					6 Months Ended
	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2022		Mar. 31, 2022	Jun. 30, 2023		Jun. 30, 2022
Segment Reporting Information [Line Items]
Revenues and other income	$ 324.0		$ 313.4			$ 629.0		$ 625.8
Net income (loss)	147.9	$ 142.2	151.8		$ 159.6	290.1		311.4
Net income (loss) attributable to Hess Midstream LP	25.1		22.0			45.8		38.9
Depreciation expense	47.0		45.0			94.4		89.4
Proportional share of equity affiliates' depreciation	1.3		1.3			2.6		2.6
Income from equity investments	1.7		1.0			3.3		1.4
Interest expense, net	43.8		37.4			85.4		68.7
Income tax expense	8.1		7.1			14.6		12.1
Adjusted EBITDA	248.1		242.6			487.1		484.2
Capital expenditures	52.1		71.7	[1]		109.4	[1]	108.8	[1]
Interest and Other
Segment Reporting Information [Line Items]
Net income (loss)	(53.9)		(46.0)			(104.5)		(84.6)
Net income (loss) attributable to Hess Midstream LP	(17.9)		(14.4)			(32.4)		(23.8)
Interest expense, net	43.8		37.4			85.4		68.7
Income tax expense	8.1		7.1			14.6		12.1
Adjusted EBITDA	(2.0)		(1.5)			(4.5)		(3.8)
Gathering Opco | Operating Segments
Segment Reporting Information [Line Items]
Revenues and other income	174.5		166.2			339.2		329.8
Net income (loss)	100.0		95.2			195.1		193.4
Net income (loss) attributable to Hess Midstream LP	21.3		17.6			38.7		30.6
Depreciation expense	28.2		26.6			57.0		52.5
Adjusted EBITDA	128.2		121.8			252.1		245.9
Capital expenditures	46.4		67.7	[1]		95.8	[1]	103.4	[1]
Processing and Storage | Operating Segments
Segment Reporting Information [Line Items]
Revenues and other income	122.8		116.5			237.2		230.3
Net income (loss)	85.1		81.3			165.2		159.4
Net income (loss) attributable to Hess Midstream LP	18.3		15.0			32.8		25.4
Depreciation expense	14.5		14.4			29.0		28.8
Proportional share of equity affiliates' depreciation	1.3		1.3			2.6		2.6
Income from equity investments	1.7		1.0			3.3		1.4
Adjusted EBITDA	100.9		97.0			196.8		190.8
Capital expenditures	2.7		1.3	[1]		3.6	[1]	2.2	[1]
Terminaling and Export | Operating Segments
Segment Reporting Information [Line Items]
Revenues and other income	26.7		30.7			52.6		65.7
Net income (loss)	16.7		21.3			34.3		43.2
Net income (loss) attributable to Hess Midstream LP	3.4		3.8			6.7		6.7
Depreciation expense	4.3		4.0			8.4		8.1
Adjusted EBITDA	21.0		25.3			42.7		51.3
Capital expenditures	$ 3.0		$ 2.7	[1]		$ 10.0	[1]	$ 3.2	[1]

[1] Includes acquisition, expansion and maintenance capital expenditures, as applicable.