Related Party Transactions - Summary of Revenues From Contracts With Customers on Disaggregated Basis (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Disaggregation Of Revenue [Line Items]
Revenue from contract with customer including assessed tax	$ 1,203.8	$ 1,091.6	$ 847.6
Other income		0.3	0.7
Total revenues	1,203.8	1,091.9	848.3
Oil and Gas Gathering Services
Disaggregation Of Revenue [Line Items]
Revenue from contract with customer including assessed tax	540.4	469.3	345.6
Processing and Storage Services
Disaggregation Of Revenue [Line Items]
Revenue from contract with customer including assessed tax	435.7	370.3	294.7
Terminaling and Export Services
Disaggregation Of Revenue [Line Items]
Revenue from contract with customer including assessed tax	137.5	159.4	130.0
Water Gathering and Disposal Services
Disaggregation Of Revenue [Line Items]
Revenue from contract with customer including assessed tax	$ 90.2	$ 92.6	$ 77.3