Related Party Transactions (Details) - USD ($)	3 Months Ended			9 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Related Party Transaction [Line Items]
Purchases of property, plant and equipment				$ 55,800,000	$ 158,800,000
Costs of product/services sold at CEQP and CMLP(2)	$ 34,800,000		$ 6,100,000	101,300,000	12,900,000
Operations and maintenance expenses charged by CEQP and CMLP	5,100,000		5,000,000.0	16,800,000	16,700,000
Related Party Transaction, Due from (to) Related Party [Abstract]
Related party receivables	7,300,000			7,300,000		$ 2,500,000
Related party payables	13,100,000			13,100,000		7,500,000
Noncash Distribution to Parent		$ 2,400,000
Applied Consultants, Inc.
Related Party Transaction [Line Items]
Purchases of property, plant and equipment				600,000	3,200,000
Crestwood Permian Basin Holdings LLC
Related Party Transaction [Line Items]
Costs of product/services sold at CEQP and CMLP(2)	30,400,000		5,700,000	75,500,000	12,100,000
Tres Palacios Holdings LLC
Related Party Transaction [Line Items]
Costs of product/services sold at CEQP and CMLP(2)	200,000		300,000	11,300,000	400,000
Ascent Resources - Utica, LLC
Related Party Transaction [Line Items]
Costs of product/services sold at CEQP and CMLP(2)	4,200,000		100,000	14,500,000	400,000
Affiliated Entity
Related Party Transaction [Line Items]
Revenues at CEQP and CMLP	7,100,000		10,900,000	25,200,000	25,900,000
Costs of product/services sold at CEQP and CMLP(2)	34,800,000		6,100,000	101,300,000	12,900,000
Related Party Transaction, Selling, General and Administrative Expenses from Transactions with Related Party	11,900,000		7,400,000	24,400,000	25,400,000
Crestwood Equity Partners LP | Affiliated Entity
Related Party Transaction [Line Items]
Related Party Transaction, Selling, General and Administrative Expenses from Transactions with Related Party			900,000	200,000	1,300,000
Related Party Transaction Selling General And Administrative Expenses To (From) Transactions With Related Party	0		1,200,000	4,800,000	12,500,000
Crestwood Midstream Partners LP
Related Party Transaction [Line Items]
Purchases of property, plant and equipment				55,800,000	158,800,000
Costs of product/services sold at CEQP and CMLP(2)	34,800,000		6,100,000	101,300,000	12,900,000
Related Party Transaction, Due from (to) Related Party [Abstract]
Related party payables	13,100,000			13,100,000		$ 5,000,000.0
Crestwood Midstream Partners LP | Affiliated Entity
Related Party Transaction [Line Items]
Related Party Transaction, Selling, General and Administrative Expenses from Transactions with Related Party	1,000,000		1,000,000	3,000,000	3,100,000
Crestwood LTIP | Crestwood Midstream Partners LP
Related Party Transaction [Line Items]
Share-based Payment Arrangement, Expense	12,900,000		8,400,000	27,400,000	28,500,000
Crestwood LTIP | Crestwood Holdings
Related Party Transaction [Line Items]
Share-based Payment Arrangement, Expense	0		300,000	4,600,000	11,200,000
Stagecoach Gas Services LLC
Related Party Transaction [Line Items]
Operations and maintenance expenses charged by CEQP and CMLP	100,000		1,700,000	3,400,000	5,000,000
Tres Palacios Holdings LLC
Related Party Transaction [Line Items]
Operations and maintenance expenses charged by CEQP and CMLP	1,200,000		900,000	3,600,000	3,100,000
Crestwood Permian Basin Holdings LLC
Related Party Transaction [Line Items]
Operations and maintenance expenses charged by CEQP and CMLP	$ 3,800,000		$ 2,400,000	$ 9,800,000	$ 8,600,000