Related Party Transactions - Summary of Classification of Charges between Operating and Maintenance Expenses and General and Administrative Expenses (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Related Party Transaction [Line Items]
Operating and maintenance expenses	$ 73.1	$ 67.8	$ 135.6	$ 134.3
Hess
Related Party Transaction [Line Items]
Operating and maintenance expenses	$ 19.5	$ 16.7	$ 37.4	$ 33.6
Operating Cost and Expense, Related and Nonrelated Party Status [Extensible Enumeration]	us-gaap:RelatedPartyMember	us-gaap:RelatedPartyMember	us-gaap:RelatedPartyMember	us-gaap:RelatedPartyMember
General and administrative expenses	$ 3.8	$ 3.8	$ 7.7	$ 7.5
Selling, General, and Administrative Expenses, Related and Nonrelated Party Status [Extensible Enumeration]	us-gaap:RelatedPartyMember	us-gaap:RelatedPartyMember	us-gaap:RelatedPartyMember	us-gaap:RelatedPartyMember
Total	$ 23.3	$ 20.5	$ 45.1	$ 41.1