Related Party Transactions (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Related Party Transaction [Line Items]
Gathering and processing revenues at CEQP and CMLP	$ 0.7	$ 1.0
General and administrative expenses charged by CEQP to Crestwood Holdings, net(3)	0.7	0.9
Affiliated Entity
Related Party Transaction [Line Items]
Related party receivables	1.1		$ 1.7
Gathering and processing revenues at CEQP and CMLP	0.7	1.0
Gathering and processing costs of product/services sold at CEQP and CMLP(1)	4.3	8.3
General and administrative expenses charged by CEQP to CMLP, net(2)	3.7	17.4
Related Party Transaction, Due from (to) Related Party [Abstract]
Accounts payable	3.8		4.0
Crestwood Equity Partners LP
Related Party Transaction [Line Items]
General and administrative expenses charged by CEQP to Crestwood Holdings, net(3)	0.1	0.1
Crestwood Midstream Partners LP
Related Party Transaction [Line Items]
Gathering and processing revenues at CEQP and CMLP	0.7	1.0
Crestwood Midstream Partners LP | Affiliated Entity
Related Party Transaction [Line Items]
Related party receivables	1.1		1.7
General and administrative expenses charged by CEQP to CMLP, net(2)	0.8
Related Party Transaction, Due from (to) Related Party [Abstract]
Accounts payable	1.3		$ 1.5
Crestwood LTIP | Crestwood Midstream Partners LP
Related Party Transaction [Line Items]
Allocated Share-based Compensation Expense	4.5	$ 2.2
Crestwood LTIP | Crestwood Holdings [Member]
Related Party Transaction [Line Items]
Allocated Share-based Compensation Expense	$ 0.1