| Document and Entity Information | Jul. 11, 2022 |
| Cover [Abstract] | |
| Document Type | 8-K/A |
| Amendment Flag | true |
| Document Period End Date | Jul. 11, 2022 |
| Entity Registrant Name | CRESTWOOD MIDSTREAM PARTNERS LP |
| Entity Incorporation, State or Country Code | DE |
| Entity File Number | 001-35377 |
| Entity Tax Identification Number | 20-1647837 |
| Entity Address, Address Line One | 811 Main Street |
| 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 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | false |
| Amendment Description | Acquisition As reported in a Current Report on Form 8-K filed with the Securities and Exchange Commission on July 15, 2022 (the “Original Form 8-K”) by Crestwood Midstream Partners LP, a Delaware limited partnership (“CMLP”), on July 11, 2022, CMLP, a wholly owned subsidiary of Crestwood Equity Partners LP, a Delaware limited partnership (the “Partnership”), and Crestwood Sendero GP LLC, a Delaware limited liability company (together with CMLP, the “Buyers”) and wholly owned subsidiary of CMLP, completed their acquisition (the “Sendero Acquisition”) of Sendero Midstream Partners LP (“Sendero”) for approximately $600 million in cash, subject to certain adjustments, pursuant to the Purchase Agreement, dated as of May 25, 2022, by and among (i) the Buyers, (ii) the Partnership, as the guarantor and indirect owner of the Buyers, (iii) Sendero, (iv) Energy Capital Partners III, LP, a Delaware limited partnership, (v) Energy Capital Partners III-A, LP, a Delaware limited partnership, (vi) Energy Capital Partners III-B (Sendero IP), LP, a Delaware limited partnership, (vii) Energy Capital Partners III-C (Sendero IP), LP, a Delaware limited partnership, (viii) Carlsbad Co-Invest, LP, a Delaware limited partnership, (ix) ECP III (Sendero Co-Invest) Corp, a Delaware corporation, (x) Sendero Midstream Management, LLC, a Delaware limited liability company, and (xi) Sendero Midstream GP, LLC, a Delaware limited liability company and the general partner of Sendero. Capitalized terms used but not defined herein will have the meanings assigned to such terms in the Original Form 8-K. This Current Report on Form 8-K/A (this “Amendment”) amends and supplements the Original Form 8-K to provide the following: • the unaudited financial statements of Sendero (for the period described in Item 9.01(a) below) and the notes thereto; • the audited financial statements of Sendero (for the period described in Item 9.01(a) below), the notes thereto and the Report of Independent Auditors; and • the unaudited pro forma condensed consolidated combined financial information described in Item 9.01(b) below. No other modifications to the Original Form 8-K are being made by this Amendment. This Amendment should be read in connection with the Original Form 8-K, which provides a more complete description of the Acquisitions. |
| Entity Central Index Key | 0001304464 |
