CONSOLIDATED STATEMENTS OF OPERATIONS (UNAUDITED) - USD ($) shares in Millions, $ in Millions		3 Months Ended
		Mar. 31, 2020	Mar. 31, 2019
Revenues
Affiliate services		$ 290.6	$ 189.4	[1]
Type of Revenue [Extensible List]		hesm:AffiliateServicesMember	hesm:AffiliateServicesMember	[1]
Other income		$ 0.2	$ 0.2	[1]
Total revenues		290.8	189.6	[1]
Costs and expenses
Operating and maintenance expenses (exclusive of depreciation shown separately below)		91.9	54.3	[1]
Depreciation expense		38.5	33.6	[1]
General and administrative expenses		7.6	5.9	[1]
Total costs and expenses		138.0	93.8	[1]
Income from operations		152.8	95.8	[1]
Income from equity investments		2.7
Interest expense, net		24.8	15.0	[1]
Income before income tax expense (benefit)		130.7	80.8	[1]
Income tax expense (benefit)		1.7
Net income		129.0	80.8	[1]
Less: Net income (loss) attributable to net parent investment	[1]		(14.5)
Less: Net income (loss) attributable to noncontrolling interest		122.5	77.2	[1]
Net income attributable to Hess Midstream LP		6.5	18.1	[1]
Less: General partner's interest in net income	[1]		0.8
Limited partners' interest in net income		$ 6.5	$ 17.3	[1]
Common Units
Net income attributable to Hess Midstream LP per limited partner unit (basic and diluted):
Net income attributable to Hess Midstream Partners per limited partner unit	[1]		$ 0.32
Weighted average limited partner units outstanding prior to the Restructuring, Basic:
Units outstanding prior to the Restructuring, Basic	[1]		27.3
Weighted average limited partner units outstanding prior to the Restructuring, Diluted:
Units outstanding prior to the Restructuring, Diluted	[1]		27.4
Subordinated Units
Net income attributable to Hess Midstream LP per limited partner unit (basic and diluted):
Net income attributable to Hess Midstream Partners per limited partner unit	[1]		$ 0.32
Weighted average limited partner units outstanding prior to the Restructuring, Basic:
Units outstanding prior to the Restructuring, Basic	[1]		27.3
Weighted average limited partner units outstanding prior to the Restructuring, Diluted:
Units outstanding prior to the Restructuring, Diluted	[1]		27.3
Class A Shares
Net income attributable to Hess Midstream LP per Class A share:
Net income attributable to Hess Midstream LP per Class A share, Basic		$ 0.37
Net income attributable to Hess Midstream LP per Class A share, Diluted		$ 0.35
Net income attributable to Hess Midstream LP per limited partner unit (basic and diluted):
Weighted average Class A shares outstanding subsequent to the restructuring, Basic		18.0
Weighted average Class A shares outstanding subsequent to the restructuring, Diluted		18.0

[1] The financial information presented in this report has been retrospectively adjusted for the acquisition of Hess Infrastructure Partners LP.