Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ (24.3)	$ 225.0	$ (47.7)	$ 239.1
Change in fair value of Suburban Propane Partners, L.P. units	0.0	0.3	(1.1)	0.7
Comprehensive income (loss)	(24.3)	225.3	(48.8)	239.8
Comprehensive income attributable to non-controlling partner	10.2	10.6	20.1	14.6
Comprehensive income (loss) attributable to Crestwood Equity Partners LP	$ (34.5)	$ 214.7	$ (68.9)	$ 225.2