v3.26.1
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
Mar. 31, 2026
Mar. 31, 2025
Related Party Transaction [Line Items]    
Operating and maintenance expenses $ 85.6 $ 85.6
Chevron    
Related Party Transaction [Line Items]    
Operating and maintenance expenses $ 17.1 $ 24.9
Operating Cost and Expense, Related Party [Extensible Enumeration] us-gaap:RelatedPartyMember us-gaap:RelatedPartyMember
General and administrative expenses $ 5.8 $ 5.0
Selling, General, and Administrative Expenses, Related Party [Extensible Enumeration] us-gaap:RelatedPartyMember us-gaap:RelatedPartyMember
Total $ 22.9 $ 29.9