Segment Information - Other Financial Information (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Other financial information [Abstract]
Total assets		$ 15,295.4		$ 15,208.2
Operating Segments [Member]
Other financial information [Abstract]
Total assets	[1]	15,295.4	$ 15,648.4
Goodwill		45.2	45.2
Capital expenditures		162.5	83.4
Operating Segments [Member] | Gathering and Processing [Member]
Other financial information [Abstract]
Total assets	[1]	7,951.0	8,635.2
Goodwill		45.2	45.2
Capital expenditures		133.0	69.5
Operating Segments [Member] | Logistics and Transportation [Member]
Other financial information [Abstract]
Total assets	[1]	7,196.0	6,743.9
Capital expenditures		25.2	10.4
Operating Segments [Member] | Other [Member]
Other financial information [Abstract]
Total assets	[1]	1.6	90.8
Operating Segments [Member] | Corporate and Eliminations [Member]
Other financial information [Abstract]
Total assets	[1]	146.8	178.5
Capital expenditures		$ 4.3	$ 3.5

[1] Assets in the Corporate and Eliminations column primarily include tax-related assets, cash, prepaids and debt issuance costs for our revolving credit facilities.