Cover Page - shares	6 Months Ended
	Jun. 30, 2020	Jul. 31, 2020
Document Information [Line Items]
Document Transition Report	false
Document Quarterly Report	true
Entity Shell Company	false
Entity Interactive Data Current	Yes
Entity Current Reporting Status	Yes
Entity Address, Address Line One	811 Main Street
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2020
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q2
Entity Registrant Name	Crestwood Equity Partners LP
Entity File Number	001-34664
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	43-1918951
Entity Central Index Key	0001136352
Current Fiscal Year End Date	--12-31
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		73,161,478
Entity Address, Address Line Two	Suite 3400
Entity Address, City or Town	Houston
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	77002
City Area Code	832
Local Phone Number	519-2200
Crestwood Midstream Partners LP
Document Information [Line Items]
Entity Shell Company	false
Entity Interactive Data Current	Yes
Entity Current Reporting Status	Yes
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2020
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q2
Entity Registrant Name	Crestwood Midstream Partners LP
Entity File Number	001-35377
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	20-1647837
Entity Central Index Key	0001304464
Current Fiscal Year End Date	--12-31
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		0
Common Units
Document Information [Line Items]
Title of 12(b) Security	Common Units representing limited partnership interests
Trading Symbol	CEQP
Security Exchange Name	NYSE
Preferred Units
Document Information [Line Items]
Title of 12(b) Security	Preferred Units representing limited partnership interests
Trading Symbol	CEQP-P
Security Exchange Name	NYSE