Earnings per Share - Schedule of Earnings per Share (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended				6 Months Ended
	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2022	Jun. 30, 2021
Limited Partners Capital Account [Line Items]
Net income	$ 151.8	$ 159.6	$ 162.0	$ 159.6	$ 311.4	$ 321.6
Less: Net income attributable to noncontrolling interest	129.8		151.0		272.5	302.0
Net income attributable to Hess Midstream LP	$ 22.0		$ 11.0		$ 38.9	$ 19.6
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	$ 0.51		$ 0.44		$ 1.01	$ 0.89
Net income attributable to Hess Midstream LP per Class A share, Diluted	$ 0.50		$ 0.44		$ 0.99	$ 0.87
Weighted average Class A shares outstanding
Weighted average Class A shares outstanding, Basic	43.7		25.0		38.7	22.2
Weighted average Class A shares outstanding, Diluted	43.7		25.1		38.8	22.3