Crestwood Equity Partners (CEQP) 10-K 2 Mar 15 2014 FY Annual report Financial data

Document_and_Entity_Informatio

Document and Entity Information (USD $)	12 Months Ended
In Billions, except Share data, unless otherwise specified	Dec. 31, 2014	Feb. 13, 2015	Jun. 30, 2014
Entity Information [Line Items]
Document Type	10-K
Amendment Flag	FALSE
Document Period End Date	31-Dec-14
Document Fiscal Year Focus	2014
Document Fiscal Period Focus	FY
Trading Symbol	CEQP
Entity Registrant Name	Crestwood Equity Partners LP
Entity Central Index Key	1136352
Current Fiscal Year End Date	-19
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		187,349,776
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Public Float			$1.60

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Assets
Cash	$8.80	$5.20
Accounts receivable, less allowance for doubtful accounts of $0.1 million at December 31, 2014 and December 31, 2013	379.6	412.6
Inventory (Note 4)	46.6	73.6
Assets from price risk management activities	79.8	14.5
Prepaid expenses and other current assets	23.3	16.1
Total current assets	538.1	522
Property, plant and equipment (Note 4)	4,273.90	4,108.70
Less: accumulated depreciation and depletion	380.1	203.4
Property, plant and equipment, net	3,893.80	3,905.30
Intangible assets (Note 4)	1,441.90	1,466.40
Less: accumulated amortization	210.6	106
Intangible assets, net	1,231.30	1,360.40
Goodwill	2,491.80	2,552.20
Investment in unconsolidated affiliates (Note 6)	295.1	151.4
Other assets	11.3	31.9
Total assets	8,461.40	8,523.20
Current liabilities:
Accounts payable	241.2	379
Accrued expenses and other liabilities (Note 4)	154.6	177.1
Liabilities from price risk management activities	25.4	34.9
Current portion of long-term debt (Note 9)	3.7	5.1
Total current liabilities	424.9	596.1
Long-term debt, less current portion (Note 9)	2,392.80	2,260.90
Other long-term liabilities	47.2	140.4
Deferred income taxes	12	17.2
Commitments and contingencies (Note 15)
Partners’ capital (Note 12):
Crestwood Equity Partners LP partners' capital (186,403,667 and 185,274,279 common units issued and outstanding at December 31, 2014 and December 31, 2013)	776.2	831.6
Interest of non-controlling partners in subsidiaries	4,808.30	4,677
Total partners’ capital	5,584.50	5,508.60
Total liabilities and partners’ capital	$8,461.40	$8,523.20

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parenthetical) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Millions, except Share data, unless otherwise specified
Allowance for doubtful accounts	$0.10	$0.10
Common units, issued	186,403,667	185,274,279
Common units, outstanding	186,403,667	185,274,279

Consolidated_Statements_of_Ope

Consolidated Statements of Operations (USD $)	12 Months Ended
In Millions, except Share data in Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Revenues:
Gathering and processing	$328.50	$216.30	$125.80
Storage and transportation	192.9	104.2	0
NGL and crude services	3,406.90	1,031.30	0
Related party (Note 16)	3	74.9	113.7
Total revenue	3,931.30	1,426.70	239.5
Costs of product/services sold:
Gathering and processing	29.1	24.1	23.8
Storage and transportation	24.8	15.7	0
NGL and crude services	3,069.20	930	0
Related party (Note 16)	42.2	32.5	15.2
Cost of product/services sold	3,165.30	1,002.30	39
Expenses:
Assets, Current	538.1	522
Operations and maintenance	203.3	104.6	43.1
General and administrative (Note 16)	100.2	93.5	29.6
Depreciation, amortization and accretion	285.3	167.9	73.2
Operating Expenses	588.8	366	145.9
Gain (loss) on long-lived assets, net	-1.9	5.3	0
Goodwill impairment	-48.8	-4.1	0
Gain (loss) on contingent consideration (Note 15)	-8.6	-31.4	6.8
Operating income	117.9	28.2	61.4
Earnings (loss) from unconsolidated affiliates, net	-0.7	-0.1	0
Interest and debt expense, net	-127.1	-77.9	-35.8
Other income, net	0.6	0.2	0
Income (loss) before income taxes	-9.3	-49.6	25.6
Provision for income taxes	1.1	1	1.2
Net income (loss)	-10.4	-50.6	24.4
Net (income) loss attributable to non-controlling partners	66.8	57.3	-9.5
Net income attributable to Crestwood Equity Partners LP	56.4	6.7	14.9
Subordinated unitholders' interest in net income	1.3	0.3	1.7
Common unitholders' interest in net income	$55.10	$6.40	$13.20
Net income per limited partner unit:
Basic (dollars per unit)	$0.30	$0.06	$0.38
Diluted (dollars per unit)	$0.30	$0.06	$0.38
Weighted-average limited partners’ units outstanding (in thousands):
Basic (units)	182,009	109,145	35,103
Dilutive units (units)	4,388	4,388	4,388
Diluted (units)	186,397	113,533	39,491

Consolidated_Statements_of_Com

Consolidated Statements of Comprehensive Income (USD $)	3 Months Ended								12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Net income (loss)	($30.70)	$11.90	($4.80)	$13.20	($42.10)	($7.90)	($4.50)	$3.90	($10.40)	($50.60)	$24.40
Change in fair value of Suburban Propane Partners, L.P. units (Note 12)									-0.5	-0.1	0
Comprehensive income (loss)									($10.90)	($50.70)	$24.40

Consolidated_Statement_of_Part

Consolidated Statement of Partners' Capital (USD $)	Total	CMLP	Crestwood Marcellus Midstream LLC	Arrow Midstream Holdings, LLC	Class D Units	Class C Units	Limited Partners	Limited Partners	Limited Partners	Limited Partners	Limited Partners	Limited Partners	Non-Controlling Partners	Non-Controlling Partners	Non-Controlling Partners	Non-Controlling Partners	Non-Controlling Partners	Non-Controlling Partners
								CMLP	Crestwood Marcellus Midstream LLC	Arrow Midstream Holdings, LLC	Class D Units	Class C Units		CMLP	Crestwood Marcellus Midstream LLC	Arrow Midstream Holdings, LLC	Class D Units	Class C Units
Balance at the beginning of the period at Dec. 31, 2011	$1,120,000,000						$22,000,000						$1,098,000,000
Increase (Decrease) in Partners' Capital [Roll Forward]
Proceeds from the issuance of common units	217,500,000						0						217,500,000
Net proceeds from issuance of common units by subsidiaries						0						2,000,000						-2,000,000
Contributions from partner	290,800,000						6,600,000						284,200,000
Unit-based compensation charges	1,900,000						0						1,900,000
Taxes paid for unit-based compensation vesting	-400,000						0						-400,000
Distributions to partners	-103,500,000						-13,800,000						-89,700,000
Change in fair value of Suburban Propane Partners, L.P. units (Note 12)	0
Net income (loss)	24,400,000						14,900,000						9,500,000
Balance at the end of the period at Dec. 31, 2012	1,550,700,000						31,700,000						1,519,000,000
Increase (Decrease) in Partners' Capital [Roll Forward]
Proceeds from the issuance of common units	714,000,000			200,000,000			0			0			714,000,000			200,000,000
Net proceeds from issuance of common units by subsidiaries					0	0					-126,300,000	600,000					126,300,000	-600,000
Contributions from partner	10,000,000						0						10,000,000
Unit-based compensation charges	17,400,000						1,700,000						15,700,000
Taxes paid for unit-based compensation vesting	-8,300,000						-2,800,000						-5,500,000
Distributions to partners	-271,100,000					0	-56,600,000					-100,000	-214,500,000					100,000
Issuance of preferred equity of subsidiary	96,100,000						0						96,100,000
Exchange of Crestwood Midstream Partners LP units for CEQP units	0						182,300,000						-182,300,000
Invested capital from Legacy Inergy, net of debt (Note 3)	3,379,400,000						697,100,000						2,682,300,000
Distribution for additional interest in Crestwood Marcellus Midstream LLC	-129,000,000						-129,000,000						0
Gain (loss) on issuance of subsidiary units	0						-12,600,000						12,600,000
Change in interest in Crestwood Marcellus Midstream LLC			0						238,900,000						-238,900,000
Change in fair value of Suburban Propane Partners, L.P. units (Note 12)	-100,000						-100,000						0
Other	100,000						100,000						0
Net income (loss)	-50,600,000						6,700,000						-57,300,000
Balance at the end of the period at Dec. 31, 2013	5,508,600,000						831,600,000						4,677,000,000
Increase (Decrease) in Partners' Capital [Roll Forward]
Proceeds from the issuance of common units	17,529,879
Contributions from partner	-15,300,000						-10,500,000						-4,800,000
Unit-based compensation charges	21,300,000						3,900,000						17,400,000
Taxes paid for unit-based compensation vesting	-3,900,000						-2,300,000						-1,600,000
Distributions to partners	-399,000,000						-102,500,000						-296,500,000
Issuance of preferred equity of subsidiary	53,900,000	430,500,000					0	0					53,900,000	430,500,000
Change in fair value of Suburban Propane Partners, L.P. units (Note 12)	-500,000						-500,000						0
Other	-700,000						100,000						-800,000
Net income (loss)	-10,400,000						56,400,000						-66,800,000
Balance at the end of the period at Dec. 31, 2014	$5,584,500,000						$776,200,000						$4,808,300,000

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Operating activities
Net income (loss)	($10.40)	($50.60)	$24.40
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion	285.3	167.9	73.2
Amortization of debt-related deferred costs, discounts and premiums	8.5	9.2	5.5
Market adjustment on interest rate swaps	-2.7	-1.7	0
Unit-based compensation charges	21.3	17.4	1.9
(Gain) loss on long-lived assets, net	1.9	-5.3	0
Goodwill impairment	48.8	4.1	0
(Gain) loss on contingent consideration	8.6	31.4	-6.8
Loss from unconsolidated affiliates, net	0.7	0.1	0
Deferred income taxes	-5.2	-2.8	0
Other	0	-1	-0.2
Changes in operating assets and liabilities, net of effects from acquisitions:
Accounts receivable	60.4	-39.9	-3.5
Inventory	26.9	-23.6	0
Prepaid expenses and other current assets	-11.4	11.2	0.8
Accounts payable, accrued expenses and other liabilities	-96.4	44.2	6.8
Reimbursements of property, plant and equipment	21.5	0	0
Net liabilities from price risk management activities	-74.8	27.7	0
Net cash provided by operating activities	283	188.3	102.1
Investing activities
Acquisitions, net of cash acquired (Note 3)	-19.5	-555.6	-564
Purchases of property, plant and equipment	-424	-347	-52.6
Investment in unconsolidated affiliates	-108.6	-151.5	0
Proceeds from sale of Tres Palacios	66.4	0	0
Proceeds from sale of assets	2.7	11.2	0
Net cash used in investing activities	-483	-1,042.90	-616.6
Financing activities
Proceeds from the issuance of long-term debt	2,823.90	2,466.90	706.7
Principal payments on long-term debt	-2,696	-1,967.60	-534
Payments on capital leases	-3.2	-4.3	-3
Payments for debt-related deferred costs	-1.9	-33.1	-11.4
Payments for deferred acquisition costs	0	0	-7.8
Contributions from partners	0	0	249.7
Distributions to partners	-102.5	-68.4	-13.8
Distributions paid to non-controlling partners	-296.5	-204.5	-89.7
Distribution for additional interest in Crestwood Marcellus Midstream LLC	0	-129	0
Net proceeds from issuance of Crestwood Midstream Partners LP common units	0	714	217.5
Net proceeds from issuance of preferred equity of subsidiary	53.9	96.1	0
Taxes paid for unit-based compensation vesting	-3.9	-10.5	-0.4
Other	-0.7	0.1	0
Net cash provided by financing activities	203.6	859.7	513.8
Net change in cash	3.6	5.1	-0.7
Cash at beginning of period	5.2	0.1	0.8
Cash at end of period	8.8	5.2	0.1
Cash paid during the period for interest	114.4	64.9	27.9
Cash paid during the period for income taxes	6.6	2.5	0
Supplemental schedule of noncash investing and financing activities
Net change to property, plant and equipment through accounts payable and accrued expenses	-40.6	-38	-1.7
Acquisitions, net of cash acquired:
Current assets	0.5	409.6	0
Property, plant and equipment	13.5	2,487.20	178
Intangible assets	9.4	660.9	384
Goodwill	3.6	2,195.40	4.1
Other assets	0	32.1	0
Current liabilities	-2.7	-420.6	-0.7
Debt	-3.5	-1,079.30	0
Invested capital of Crestwood Equity Partners LP, net of debt (Note 3)	0	-3,579.40	0
Other liabilities	-1.3	-150.3	-1.4
Total acquisitions, net of cash acquired	19.5	555.6	564
Preferred Units, Class A
Financing activities
Net proceeds from issuance of preferred equity of subsidiary	$430.50	$0	$0

Basis_of_Presentation_and_Summ

Basis of Presentation and Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2014
Accounting Policies [Abstract]
Basis of Presentation and Summary of Significant Accounting Policies	Basis of Presentation and Summary of Significant Accounting Policies
	Basis of Presentation
	Our consolidated financial statements were originally the financial statements of Legacy Crestwood GP, prior to being acquired by us on June 19, 2013. The acquisition of Legacy Crestwood GP was accounted for as a reverse acquisition under the purchase method of accounting in accordance with accounting standards for business combinations. The accounting for the reverse acquisition resulted in the legal acquiree (Legacy Crestwood GP) being the acquirer for accounting purposes. Although Legacy Crestwood GP was the acquiring entity for accounting purposes, we were the acquiring entity for legal purposes.
	Our consolidated financial statements are prepared in accordance with GAAP and include the accounts of all consolidated subsidiaries after the elimination of all intercompany accounts and transactions. Our consolidated financial statements for prior periods include reclassifications that were made to conform to the current year presentation, none of which impacted our previously reported net income, earnings per unit or partners' capital. In management’s opinion, all necessary adjustments to fairly present our results of operations, financial position and cash flows for the periods presented have been made and all such adjustments are of a normal and recurring nature.
	Principles of Consolidation
	We consolidate entities when we have the ability to control or direct the operating and financial decisions of the entity or when we have a significant interest in the entity that gives us the ability to direct the activities that are significant to that entity. The determination to consolidate or apply the equity method of accounting to an entity can also require us to evaluate whether that entity is considered a variable interest entity. This evaluation, along with the determination of our ability to control, direct or exert significant influence over an entity involves the use of judgment. We apply the equity method of accounting where we can exert significant influence over, but do not control or direct the policies, decisions or activities of an entity. We use the cost method of accounting where we are unable to exert significant influence over the entity.
	In December 2014, we sold our 100% interest in Tres Palacios Gas Storage Company LLC (Tres Palacios) to Tres Palacios Holdings LLC (Tres Holdings), a newly formed joint venture between Crestwood Midstream and an affiliate of Brookfield Infrastructure Group (Brookfield); consequently, we deconsolidated Tres Palacios and began accounting for the investment in Tres Holdings under the equity method of accounting through our indirect ownership in Crestwood Midstream. See Note 6 for additional information related to the sale of Tres Palacios.
	Use of Estimates
	The preparation of our consolidated financial statements in conformity with GAAP requires the use of estimates and assumptions that affect the amounts we report as assets, liabilities, revenues and expenses and our disclosures in these consolidated financial statements. Actual results can differ from those estimates.
	Cash
	We consider all highly liquid investments with an original maturity of less than three months to be cash.
	Inventory
	Inventory for our NGL and crude services operations and our storage and transportation operations are stated at the lower of cost or market and are computed predominantly using the average cost method.
	Property, Plant and Equipment
	Property, plant and equipment is recorded at is original cost of construction or, upon acquisition, at the fair value of the assets acquired. For assets we construct, we capitalize direct costs, such as labor and materials, and indirect costs, such as overhead and interest. We capitalize major units of property replacements or improvement and expense minor items. Depreciation is computed by the straight-line method over the estimated useful lives of the assets, as follows:
		Years
	Gathering systems and pipelines	20
	Facilities and equipment	20 – 25
	Buildings, rights-of-way and easements	20 – 40
	Office furniture and fixtures	5 – 10
	Vehicles	5
	We deplete salt deposits included in our property, plant and equipment utilizing the unit of production method.
	When we retire property, plant and equipment, we charge accumulated depreciation for the original costs of the assets in addition to the cost to remove, sell or dispose of the assets, less their salvage value.
	We evaluate our long-lived assets for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. If such events or changes in circumstances are present, a loss is recognized if the carrying value of the asset is in excess of the sum of the undiscounted cash flows expected to result from the use of the asset and its eventual disposition. An impairment loss is measured as the amount by which the carrying amount of the asset exceeds the fair value of the asset, which is based on discounted cash flow projections, which is a Level 3 fair value measurement. Based on this evaluation, during the year ended December 31, 2014, we recorded a $13.2 million impairment in gain (loss) on long-lived assets in our consolidated statements of operations related to the property, plant and equipment of our gathering and processing assets located in the Granite Wash, which resulted from an announcement during the fourth quarter of 2014 by our major customer of those assets that they would cease any substantial drilling in the Granite Wash in the near future given current and future anticipated market conditions related to natural gas, which negatively impacted our future cash flows related to these operations. We had approximately $20.2 million of property, plant and equipment related to our gathering and processing operations located in the Granite Wash as of December 31, 2014, which represents the fair value of those assets based on its projected cash flows over the useful lives of the assets of 17 years and a discount rate of 9.0%, which are Level 3 fair value measurements. We did not record any impairments of our long-lived assets during the years ended December 31, 2013 and 2012 based on this evaluation.
	Identifiable Intangible Assets
	Our identifiable intangible assets consist of customer accounts, covenants not to compete, trademarks, certain revenue contracts and deferred financing costs. Customer accounts, covenants not to compete, trademarks and certain of our revenue contracts have arisen from acquisitions. We amortize certain of our revenue contracts based on the projected cash flows associated with these contracts if the projected cash flows are reliably determinable, otherwise we amortize our revenue contracts on a straight-line basis.  Deferred financing costs represent financing costs incurred in obtaining financing and are being amortized over the term of the related debt using a method which approximates the effective interest method and has a weighted average life of six years. We recognize acquired intangible assets separately if the benefit of the intangible asset is obtained through contractual or other legal rights, or if the intangible asset can be sold, transferred, licensed, rented or exchanged, regardless of the acquirer's intent to do so. For the year ended December 31, 2014, we recorded a $21.3 million impairment of our intangible assets in gain (loss) on long-lived assets in our consolidated statements of operations. This impairment was based on the intangible assets’ fair value, estimated primarily by utilizing discounted cash flow projections, which is a Level 3 fair value measurement.  This impairment was primarily related to a full impairment of our intangible assets associated with our gathering and processing operations located in the Granite Wash. This impairment resulted from an announcement in the fourth quarter of 2014 by our major customer of those assets that they would cease any substantial drilling in the Granite Wash in the near future given current and future anticipated market conditions related to natural gas in the Granite Wash.
	Certain intangible assets are amortized on a straight-line basis over their estimated economic lives, as follows:
		Weighted-Average
		Life
		(years)
	Customer accounts	22
	Covenants not to compete	5
	Trademarks	6
	Goodwill
	Our goodwill represents consideration paid in excess of the fair value of the identifiable assets acquired in a business combination. We evaluate goodwill for impairment annually on December 31, and whenever events indicate that the fair value of a reporting unit could be less than its carrying amount. This evaluation requires us to compare the fair value of a reporting unit to its carrying value (including goodwill). If the fair value exceeds the carrying amount, goodwill of the reporting unit is not considered impaired. For a further discussion of the goodwill recorded during the year ended December 31, 2014, see Note 3.
	We estimate the fair value of our reporting units based on a number of factors, including the potential value we would receive if we sold the reporting unit, discount rates and projected cash flows, which are Level 3 fair value measurements. Estimating projected cash flows requires us to make certain assumptions as it relates to future operating performance. When considering operating performance, various factors are considered such as current and changing economic conditions and the commodity price environment, among others. Due to the imprecise nature of these projections and assumptions, actual results can and often do, differ from our estimates. If the growth assumptions utilized in the current year impairment analysis prove inaccurate, we could incur an impairment charge.
	For the year ended December 31, 2014, we recorded an impairment of goodwill of approximately $48.8 million related to four of our 14 reporting units including Granite Wash (G&P), Fayetteville (G&P), US Salt (NGL and Crude Services), and Watkins Glen (NGL and Crude Services).  The $14.2 million and $4.3 million impairments of our Granite Wash and Fayetteville goodwill, respectively, resulted from a decrease in anticipated revenues to be generated from those operations due to our primary customers in those operations announcing the cessation of any significant drilling in the near future given current and future anticipated market conditions in those areas.  The $2.2 million impairment of our US Salt goodwill resulted from a decrease in anticipated revenues to be generated from those operations due primarily to the loss of a significant customer in 2014.  The $28.1 million impairment of our Watkins Glen goodwill resulted from delays and related uncertainty in the permitting of our proposed NGL storage facility. We had approximately $72.5 million, $12.6 million and $66.2 million of goodwill remaining on our consolidated balance sheet as of December 31, 2014 related to our Fayetteville, US Salt and Watkins Glen reporting units, respectively, which represents the fair value of the goodwill related to those reporting units at December 31, 2014, which is a Level 3 fair value measurement.
	For the year ended December 31, 2013, we recorded an impairment of goodwill of approximately $4.1 million on our Haynesville/Bossier Shale system as a result of a decrease in anticipated revenues to be generated from those operations due primarily to our inability to renew and extend a significant revenue contract that expired in mid-2013.
	Investment in Unconsolidated Affiliates
	We evaluate our equity method investments for impairment when events or circumstances indicate that the carrying value of the equity method investment may be impaired. If an event occurs, we evaluate the recoverability of our carrying value based on the fair value of the investment. If an impairment is indicated, or if we decide to sell an investment in unconsolidated affiliate, we adjust the carrying values of the asset downward, if necessary, to their estimated fair values. Our fair value estimates are generally based on assumptions market participants would use, including marketing data obtained through the sales process.
	Asset Retirement Obligations
	An asset retirement obligation (ARO) is an estimated liability for the cost to retire a tangible asset. We record a liability for legal or contractual obligations to retire our long-lived assets associated with right-of-way contracts we hold and our facilities whether owned or leased. We record a liability in the period the obligation is incurred and estimable. An ARO is initially recorded at its estimated fair value with a corresponding increase to property, plant and equipment. This increase in property, plant and equipment is then depreciated over the useful life of the asset to which that liability relates. An ongoing expense is recognized for changes in the fair value of the liability as a result of the passage of time, which we record as depreciation, amortization and accretion expense on our consolidated statements of operations. The fair value of certain AROs could not be determined as the settlement dates (or range of dates) associated with these assets were not estimable. At December 31, 2014 and 2013, our AROs were reflected in other long-term liabilities on our consolidated balance sheets. See Note 5 for a further discussion of our AROs.
	Revenue Recognition
	We gather, treat, compress, store, transport and sell various commodities (including crude oil, natural gas, NGLs and water) pursuant to fixed-fee and percent-of-proceeds contracts. We recognize revenues for these services and products when all of the following criteria are met:
	• services have been rendered or products delivered or sold;
	• persuasive evidence of an exchange arrangement exists;
	• the price for services is fixed or determinable; and
	• collectability is reasonably assured.
	For fixed-fee contracts, we recognize revenues based on the volume of crude oil, natural gas or produced water gathered, processed and treated or compressed, as applicable. For percent-of-proceeds contracts, we recognize revenues based on the value of products sold to third parties.
	Sales of crude oil, NGLs and salt are recognized at the time product is shipped or delivered to the customer depending on the sales terms. NGL processing and fractionation fees are recognized upon delivery of the product. Revenues from the COLT Hub are recognized when the contractual services are provided, such as loading of customer rail cars. Revenues from storage and transportation contracts are recognized during the period in which the storage and transportation services are provided, such as providing storage and transportation services during the period a firm service contract is in place. We record deferred revenue when we receive amounts from our customers but have not met the criteria listed above. We recognize deferred revenue in our consolidated statements of operations when the criteria has been met and all services have been rendered. At December 31, 2014 and 2013
	, we had deferred revenue of approximately
	$12.2 million and $2.1 million, which is reflected in accrued expenses and other liabilities on our consolidated balance sheets.
	Credit Risk and Concentrations
	Inherent in our contractual portfolio are certain credit risks. Credit risk is the risk of loss from nonperformance by suppliers, customers or financial counterparties to a contract. We take an active role in managing credit risk and have established control procedures, which are reviewed on an ongoing basis. We attempt to minimize credit risk exposure through credit policies and periodic monitoring procedures as well as through customer deposits, letters of credit and entering into netting agreements that allow for offsetting counterparty receivable and payable balances for certain financial transactions, as deemed appropriate.
	Income Taxes
	We are a master limited partnership. Partnerships are generally not subject to federal income tax, although publicly-traded partnerships are treated as corporations for federal income tax purposes and therefore are subject to federal income tax, unless the partnership generates at least 90% of its gross income from qualifying sources. If the qualifying income requirement is satisfied, the publicly-traded partnership will be treated as a partnership for federal income tax purposes. We satisfy the qualifying income requirement and are treated as a partnership for federal and state income tax purposes. Our consolidated earnings are included in the federal and state income tax returns of our partners. However, legislation in certain states allows for taxation of partnerships, and as such, certain state taxes have been included in our accompanying financial statements as income taxes due to the nature of the tax in those particular states as discussed below. In addition, federal and state income taxes are provided on the earnings of the subsidiaries incorporated as taxable entities. We are required to recognize deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the financial statements or tax returns. Under this method, deferred tax assets and liabilities are determined based on the differences between the financial reporting and tax basis of assets and liabilities using expected rates in effect for the year in which the differences are expected to reverse.
	We are responsible for the Texas Margin tax computed on the Texas franchise tax returns. The margin tax qualifies as an income tax under GAAP, which requires us to recognize the impact of this tax on the temporary differences between the financial statement assets and liabilities and their tax basis attributable to such tax.
	Net earnings for financial statement purposes may differ significantly from taxable income reportable to unitholders as a result of differences between the tax basis and the financial reporting basis of assets and liabilities and the taxable income allocation requirements under the partnership agreement.
	Environmental Costs and Other Contingencies
	We recognize liabilities for environmental and other contingencies when there is an exposure that indicates it is both probable that a liability has been incurred and the amount of loss can be reasonably estimated. Where the most likely outcome of a contingency can be reasonably estimated, we accrue a liability for that amount. Where the most likely outcome cannot be estimated, a range of potential losses is established and if no one amount in that range is more likely than any other, the low end of range is accrued.
	We record liabilities for environmental contingencies at their undiscounted amounts on our consolidated balance sheets as accrued expenses and other liabilities when environmental assessments indicate that remediation efforts are probable and costs can be reasonably estimated. Estimates of our liabilities are based on currently available facts and presently enacted laws and regulations, taking into consideration the likely effects of other societal and economic factors. These estimates are subject to revision in future periods based on actual costs or new circumstances. We capitalize costs that benefit future periods and recognize a current period charge in operations and maintenance expenses when clean-up efforts do not benefit future periods.
	We evaluate potential recoveries of amounts from third parties, including insurance coverage, separately from our liability. Recovery is evaluated based on the solvency of the third party, among other factors. When recovery is assured, we record and report an asset separately from the associated liability on our consolidated balance sheet.
	Price Risk Management Activities
	We utilize certain derivative financial instruments to (i) manage our exposure to commodity price risk, specifically, the related change in the fair value of inventory, as well as the variability of cash flows related to forecasted transactions; (ii) ensure the availability of adequate physical supply of commodity; and (iii) manage our exposure to the interest rate risk associated with fixed and variable rate borrowings. We record all derivative instruments on the balance sheet at their fair values as either assets or liabilities measured at fair value. Changes in the fair value of these derivative financial instruments are recorded through current earnings.
We did not have any derivatives identified as fair value hedges for accounting purposes or any derivatives designated as cash flow hedges for the years ended December 31, 2014, 2013 or 2012.
Unit-Based Compensation
Long-term incentive awards are granted under the Crestwood Equity and Crestwood Midstream incentive plans. Unit-based compensation awards consist of restricted units that are valued at the closing market price of CEQP's or CMLP's common units on the date of grant, which reflects the fair value of such awards. For those awards that are settled in cash, the associated liability is remeasured at every balance sheet date through settlement, such that the vested portion of the liability is adjusted to reflect its revised fair value through compensation expense. We generally recognize the expense associated with the award over the vesting period.
Prior to the Crestwood Merger, Legacy Crestwood issued phantom units under its Fourth Amended and Restated 2007 Equity Plan (2007 Equity Plan). The 2007 Equity Plan was terminated in conjunction with the Crestwood Merger. See Note 13 for a further discussion of our long-term incentive plans.
New Accounting Pronouncements Issued But Not Yet Adopted
As of December 31, 2014, the following accounting standards had not yet been adopted by us.
In May 2014, the FASB issued Accounting Standards Update 2014-09, Revenue from Contracts with Customers, which outlines a single comprehensive model for entities to use in accounting for revenue arising from contracts with customers and supersedes current revenue recognition guidance. We expect to adopt the provisions of this standard effective January 1, 2017 and are currently evaluating the impact that this standard will have on our financial statements.
In February 2015, the FASB issued Accounting Standards Update 2015-02, Consolidation (Topic 810): Amendments to the Consolidation Analysis, which provides additional guidance on the consolidation of limited partnerships and on the evaluation of variable interest entities. We expect to adopt the provisions of this standard effective January 1, 2016 and are currently evaluating the impact, if any, that this standard may have on our financial statements.

Organization_and_Description_o

Organization and Description of Business	12 Months Ended
	Dec. 31, 2014
Disclosure Partnership Organization And Basis Of Presentation Narrative [Abstract]
Organization and Description of Business	Organization and Description of Business
	Organization
	Crestwood Equity Partners LP (the Company or CEQP), is a publicly-traded (NYSE: CEQP) Delaware limited partnership formed in March 2001, that provides midstream solutions to customers in the crude oil, NGLs and natural gas sectors of the energy industry. We are engaged primarily in the gathering, processing, storage and transportation of natural gas and NGLs, the marketing of NGLs, and the gathering, storage and transportation of crude oil.
	Our general partner, Crestwood Equity GP LLC, owns our non-economic general partnership interest. Our general partner is indirectly owned by Crestwood Holdings LLC (Crestwood Holdings), which is substantially owned and controlled by First Reserve Management, L.P. (First Reserve). As of December 31, 2014, First Reserve owns approximately 27% of our common units, 4,387,889 of our subordinated units, and approximately 11% of the Crestwood Midstream Partners LP (Crestwood Midstream) common units.
	We indirectly own Crestwood Midstream GP LLC, the non-economic general partner of Crestwood Midstream and, consequently, manage and control Crestwood Midstream. As of December 31, 2014, we also own approximately 4% of Crestwood Midstream’s limited partnership interests and 100% of its incentive distribution rights (IDRs), which entitle us to receive 50% of all distributions paid by Crestwood Midstream in excess of its initial quarterly distribution of $0.37 per common unit.
	On October 7, 2013, we changed our name from Inergy, L.P. to Crestwood Equity Partners LP. Unless otherwise indicated, references in this report to “we,” “us,” “our,” “ours,” “our company,” the “partnership,” the “Company,” “Crestwood,” and similar terms refer to either Crestwood Equity Partners LP itself or Crestwood Equity Partners LP and its consolidated subsidiaries, as the context requires. Unless otherwise indicated, references to (i) the Crestwood Merger refers to the October 7, 2013 merger of the Company’s wholly-owned subsidiary with and into Legacy Crestwood, with Inergy Midstream continuing as the surviving legal entity; (ii) Legacy Inergy refers to either Inergy, L.P. itself or Inergy, L.P. and its consolidated subsidiaries prior to the Crestwood Merger, (iii) Inergy Midstream and NRGM refer to either Inergy Midstream, L.P. itself or Inergy Midstream, L.P. and its consolidated subsidiaries prior to the Crestwood Merger, (iv) Legacy Crestwood and Legacy CMLP refer to either Crestwood Midstream Partners LP itself or Crestwood Midstream Partners LP and its consolidated subsidiaries prior to the Crestwood Merger, and (v) Crestwood Midstream refers to Crestwood Midstream Partners LP and its consolidated subsidiaries following the Crestwood Merger. See Note 3 for additional information on the Crestwood Merger.
	Business Combination
	On May 5, 2013, we and certain of our affiliates entered into a series of definitive agreements with Crestwood Holdings and certain of its affiliates under which, among other things, (i) we agreed to distribute to our common unitholders all of the NRGM common units owned by us; (ii) Crestwood Holdings agreed to acquire the owner of our general partner; (iii) Crestwood Holdings agreed to contribute ownership of Legacy CMLP's general partner and IDRs to us in exchange for common and subordinated units; and (iv) Legacy Crestwood agreed to merge with and into a subsidiary of Inergy Midstream in a merger in which Legacy CMLP unitholders received 1.07 NRGM common units for each Legacy CMLP common unit they owned and, Legacy CMLP unitholders (other than Crestwood Holdings), received a one-time $34.9 million cash payment at the closing of the Crestwood Merger, or $1.03 per unit, $24.9 million of which was paid by NRGM and $10 million of which was paid by Crestwood Holdings.
	On June 5, 2013, Legacy Crestwood's general partner distributed to a wholly-owned subsidiary of Crestwood Holdings approximately 137,105 common units and approximately 21,588 Class D units of Legacy CMLP, representing all of the Legacy CMLP common and Class D units held by Legacy Crestwood's general partner.
	On June 18, 2013, we distributed to our unitholders approximately 56.4 million NRGM common units, representing all of the NRGM common units held by us.
	On June 19, 2013, Crestwood Holdings acquired the owner of our general partner and contributed to us ownership of Crestwood Gas Services GP, LLC (Legacy Crestwood GP), which owned 100% of the general partnership interests and IDRs of Legacy Crestwood. Crestwood Holdings and its ultimate parent company, First Reserve, acquired control of us as a result of these transactions.
	Following the closing of the Crestwood Merger on October 7, 2013, Crestwood Holdings exchanged 7,100,000 common units of Crestwood Midstream for 14,300,000 of our common units pursuant to an option granted to Crestwood Holdings when it acquired our general partner.
	Description of Business
	We provide gathering, processing, storage and transportation solutions to customers in the crude oil, NGL and natural gas sectors of the energy industry. Our financial statements reflect three operating and reporting segments, including:
	•	Gathering and Processing: our gathering and processing (G&P) operations provide natural gas gathering, processing, treating, compression and transportation services and sales of natural gas and the delivery of NGLs to producers in unconventional shale plays and tight-gas plays in West Virginia, Wyoming, Texas, Arkansas, New Mexico and Louisiana. This segment primarily includes our rich gas gathering systems and processing plants in the Marcellus, Powder River Basin (PRB) Niobrara, Barnett, and Permian Shale plays, and our dry gas gathering systems in the Barnett, Fayetteville, and Haynesville Shale plays.
	•	Storage and Transportation: our storage and transportation operations provide regulated natural gas storage and transportation services to producers, utilities and other customers. This segment primarily includes our natural gas storage facilities (Stagecoach, Thomas Corners, Steuben and Seneca Lake), and our natural gas transmission facilities (the North-South Facilities, the MARC I Pipeline, and the East Pipeline) in New York and Pennsylvania.
	•	NGL and Crude Services: our NGL and crude services operations provide NGL and crude oil gathering, storage, marketing and transportation services to producers, refiners, marketers, and other customers. This segment primarily includes our NGL marketing, supply and logistics business (including our West Coast processing and fractionation operations, Seymour NGL storage facility, and our fleet of terminals and over-the-road and rail transportation assets) and our integrated Bakken crude oil footprint in North Dakota, which consists of (i) the COLT Hub, a crude oil rail loading and storage terminal, (ii) the Arrow crude oil, natural gas and water gathering systems, and (iii) our fleet of over-the-road crude and produced water transportation assets. This segment also includes our Bath storage facility and US Salt, a solution-mining and salt production company in New York.
	We own and operate a proprietary NGL supply and logistics business (including our West Coast processing and fractionation facility, Seymour storage facility, terminals and transportation fleet). All of our other consolidated assets are owned by or through Crestwood Midstream.

Acquisitions

Acquisitions	12 Months Ended
	Dec. 31, 2014
Business Combinations [Abstract]
Acquisitions	Acquisitions
	2014 Acquisitions
	Crude Transportation Acquisitions (Bakken)
	Red Rock. On March 21, 2014, Crestwood Midstream purchased substantially all of the operating assets of Red Rock Transportation Inc. (Red Rock) for approximately $13.8 million, comprised of $12.1 million paid at closing plus deferred payments of $1.8 million. Red Rock is a trucking operation located in Watford City, North Dakota which provides crude oil and produced water hauling services to the oilfields of western North Dakota and eastern Montana. The acquired assets include a fleet of approximately 56 trailer tanks, 22 double bottom body tanks and 44 tractors with 28,000 barrels per day of transportation capacity. We finalized the purchase price and allocated approximately $10.6 million of the purchase price to property, plant and equipment and intangible assets and approximately $3.2 million to goodwill. Goodwill recognized relates primarily to anticipated operating synergies between the assets acquired and our existing assets. These assets are included in our NGL and crude services segment.
	LT Enterprises. On May 9, 2014, Crestwood Midstream purchased substantially all of the operating assets of LT Enterprises, Inc. (LT Enterprises) for approximately $10.7 million, comprised of $9.0 million paid at closing plus deferred payments of $1.7 million. LT Enterprises is a trucking operation located in Watford City, North Dakota which provides crude oil and produced water hauling services primarily to the oilfields of western North Dakota. The acquired assets include a fleet of approximately 38 tractors, 51 crude trailers and 17 service vehicles with 20,000 barrels per day of transportation capacity. In addition, Crestwood Midstream acquired employee housing and 20 acres of greenfield real property located two miles south of Watford City. We finalized the purchase price and allocated all of the purchase price to property, plant and equipment and intangible assets. These assets are included in our NGL and crude services segment.
	The acquisitions of Red Rock and LT Enterprises were not material to our NGL and crude services segment's results of operations for the year ended December 31, 2014. In addition, transaction costs related to these acquisitions were not material for the year ended December 31, 2014.
	2013 Acquisitions
	Crestwood Merger
	As described in Note 2, the acquisition of Legacy Crestwood GP was accounted for as a reverse merger under the purchase method of accounting in accordance with the accounting standards for business combinations. This accounting treatment requires the accounting acquiree (CEQP) to have its assets and liabilities stated at fair value as well as any other purchase accounting adjustments as of June 19, 2013, the date of the acquisition. The fair value of CEQP was calculated based on the consolidated enterprise fair value of CEQP as of June 19, 2013. This consolidated enterprise fair value considered Legacy Inergy and Inergy Midstream's (i) discounted future cash flows based on their operations; (ii) the stock prices of NRGY and NRGM; (iii) the value of their outstanding senior notes based on quoted market prices for same or similar issuances; (iv) the value of their outstanding floating rate debt; and (v) the value of IDRs of Crestwood Midstream.
	In June 2014, we finalized the Legacy Inergy purchase price allocation. The following table summarizes the final valuation of the assets acquired and liabilities assumed at the merger date (in millions):
	Current assets	$	224.5
	Property, plant and equipment	2,088.10
	Intangible assets	337.5
	Other assets	12.7
	Total identifiable assets acquired	2,662.80
	Current liabilities	207.6
	Long-term debt	1,079.30
	Other long-term liabilities	146.6
	Total liabilities assumed	1,433.50
	Net identifiable assets acquired	1,229.30
	Goodwill	2,134.80
	Net assets acquired	$	3,364.10
	Reductions of approximately $15.3 million from our preliminary estimates as of December 31, 2013 relate primarily to goodwill and were based on additional valuation information obtained on the components that comprise the enterprise fair value of Legacy Inergy as well as certain of our storage and transportation assets and obligations, primarily related to our Tres Palacios storage operations, which we previously consolidated. Of the $2,134.8 million of goodwill, $1,408.5 million is reflected in our NGL and crude services segment and $726.3 million is reflected in our storage and transportation segment. Goodwill recognized relates primarily to synergies and new expansion opportunities expected to result from the combination of Legacy Crestwood and Legacy Inergy. During 2014, we recorded impairments of goodwill for certain of our reporting units acquired in the Crestwood Merger. See Note 2 for a further discussion of our goodwill impairments.
	During the period from June 19, 2013 to December 31, 2013, we recognized $916.7 million of operating revenues and $23.9 million of operating income related to this reverse acquisition. Transaction costs related to the Crestwood Merger were $3.4 million and $30.1 million for the years ended December 31, 2014 and 2013. These costs are reflected in general and administrative expenses in our consolidated statements of operations.
	Arrow Acquisition
	On November 8, 2013, Crestwood Midstream acquired Arrow Midstream Holdings, LLC (Arrow), a privately-held midstream company, for approximately $750 million, subject to customary capital expenditure and working capital adjustments of approximately $11.3 million, representations, warranties and indemnifications.  The acquisition was consummated by merging a wholly-owned subsidiary of Crestwood Midstream with and into Arrow (the Arrow Acquisition), with Arrow continuing as the surviving entity and as a result, a wholly-owned subsidiary of Crestwood Midstream. The base merger consideration consisted of $550 million in cash and 8,826,125 common units of Crestwood Midstream issued to the sellers, subject to adjustment for standard working capital provisions.
	Arrow, through its wholly-owned subsidiaries, owns and operates substantial crude oil, natural gas and water gathering systems located on the Fort Berthold Indian Reservation in the core of the Bakken Shale in McKenzie and Dunn Counties, North Dakota. Arrow also owns salt water disposal wells and a 23-acre central delivery point with multiple pipeline take-away outlets and a fully-automated truck loading facility.
	In June 2014, we finalized the Arrow Acquisition purchase price allocation. The following table summarizes the final valuation of the assets acquired and liabilities assumed at the acquisition date (in millions):
	Current assets	$	192.7
	Property, plant and equipment	400.5
	Intangible assets	323.4
	Other assets	19.5
	Total identifiable assets acquired	936.1
	Current liabilities	215.8
	Assets retirement obligations	1.2
	Other long-term liabilities	3.7
	Total liabilities assumed	220.7
	Net identifiable assets acquired	715.4
	Goodwill	45.9
	Net assets acquired	$	761.3
	The $45.9 million of goodwill is reflected in our NGL and crude services segment. Goodwill recognized relates primarily to anticipated operating synergies between the assets acquired and our existing assets.  During the year ended December 31, 2013, we recognized $218.8 million of operating revenues and $1.7 million of operating income related to this acquisition. Transaction costs related to the Arrow Acquisition were approximately $5.4 million and $1.2 million, for the years ended December 31, 2014 and 2013. These costs are included in general and administrative expenses in our consolidated statements of operations.
	2012 Acquisitions
	Antero Acquisition
	On March 26, 2012, Crestwood Marcellus Midstream LLC (CMM) acquired from Antero gathering assets located in Harrison and Doddridge Counties, West Virginia (the Antero Acquisition) for approximately $376.8 million. The acquired assets consisted of a 33-mile low-pressure gathering system that delivers Antero’s Marcellus Shale production to various regional pipeline systems and MarkWest Energy Partners’ Sherwood Gas Processing Plant.
	In connection with the Antero Acquisition, Legacy Crestwood agreed to pay Antero conditional consideration in the form of potential additional cash payments of up to $40.0 million, depending on the achievement of certain defined average annual production levels achieved during 2012, 2013 and 2014. During 2012 and 2013, Antero did not meet the annual production level to earn additional payments. Based on our estimates of Antero’s 2014 production, we believed their production levels would exceed the annual production threshold in the earn-out provision and accordingly, we recognized a liability of $40.0 million and $31.4 million as of December 31, 2014 and 2013 that represented the fair value of the potential payments under the earn-out provision. We estimated the liability at December 31, 2013 based on the probability-weighted discounted cash flows using a 5.9% discount rate and our estimate of Antero’s production in 2014 (a Level 3 fair value measurement). In the first quarter of 2015, we expect to pay Antero $40.0 million under the earn-out provision.
	Upon the closing of the Antero Acquisition, CMM entered into a 20-year fixed-fee, Gas Gathering and Compression Agreement (GGA) with Antero. The GGA provided for an area of dedication of approximately 127,000 gross acres, or 104,000 net acres, largely located in the rich gas corridor of the southwestern core of the Marcellus Shale play. Under the GGA, Antero committed to deliver minimum annual throughput volumes to us for a seven year period from January 1, 2012 to January 1, 2019, ranging from an average of 300 MMcf/d in 2012 to an average of 450 MMcf/d in 2018. During the period ended December 31, 2012, Antero delivered less than the minimum annual throughput volumes and at December 31, 2012, we recorded a receivable and deferred revenue of approximately $2.6 million due to Antero’s potential ability to recover this amount if Antero’s 2013 throughput volumes exceeded the minimum annual throughput volumes included in the GGA for 2013. In 2013, Antero paid us approximately $2.4 million to satisfy their minimum volume commitment. For the year ended December 31, 2013, Antero's throughput volumes exceeded the 2013 minimum thresholds and was sufficient to recover their 2012 minimum volume shortfall that was previously paid. As a result of Antero's recovery of their 2012 shortfall, we reclassified approximately $2.4 million from deferred revenue to other accounts payable at December 31, 2013 to reflect the amount we owed to Antero, which was paid in 2014. We reflect deferred revenue and other accounts payable as accrued expenses and other liabilities on our consolidated balance sheets.
	Devon Acquisition
	On August 24, 2012, we acquired certain gathering and processing assets in the NGL rich gas region of the Barnett Shale (the Devon Acquisition) from Devon Energy Corporation (Devon). We paid approximately $87.3 million for these assets. During the year ended December 31, 2013, we finalized the purchase price allocation of the assets acquired and liabilities assumed, and as a result, we reduced our depreciation, amortization and accretion expense by approximately $2.2 million.
	The final purchase price allocation is as follows (in millions):
	Cash	$	87.9
	Total purchase price	$	87.9
	Purchase price allocation:
	Property, plant and equipment	$	88.6
	Total assets	88.6
	Asset retirement obligation	0.5
	Environmental liability	0.2
	Total liabilities	0.7
	Total	$	87.9
	Operating revenues, operating income and transaction costs related to the Devon Acquisition were immaterial to our results of operations for the year ended December 31, 2012. We believe that it is impracticable to present financial information for the acquired assets prior to the acquisition date due to the lack of availability of historical financial information related to the acquired assets, and because the 20-year fixed-fee gathering, processing and compression agreement with Devon has significantly different terms than the historical intercompany relationships between the acquired assets and Devon.
	EMAC Acquisition
	On December 28, 2012, CMM acquired all of the membership interest of E. Marcellus Asset Company, LLC (EMAC) from Enerven Compression, LLC (Enerven) for approximately $95.0 million. We financed this acquisition through CMM's credit facility. At the time of acquisition, EMAC’s assets consisted of four compression and dehydration stations located on our gathering systems in Harrison County, West Virginia. These assets provide compression and dehydration services to Antero under a compression services agreement through 2018. Antero has the option to renew the agreement for an additional five years upon expiration of the original agreement.
	During the year ended December 31, 2013, we finalized the purchase price allocation of the assets acquired and liabilities assumed, and as a result, we reduced our depreciation, amortization and accretion expense by approximately $0.7 million. In addition, we recognized goodwill of approximately $8.6 million, primarily related to anticipated operating synergies between the assets acquired and our existing assets.
	The final purchase price allocation is as follows (in millions):
	Cash	$	95
Total purchase price	$	95
Purchase price allocation:
Property, plant and equipment	$	53.4
Intangible assets	33.9
Goodwill	8.6
Total assets	95.9
Asset retirement obligation	0.8
Environmental liability	0.1
Total liabilities	0.9
Total	$	95
Our intangible assets recorded as a result of the EMAC acquisition relate to the compression services agreements with Antero. These intangibles will be amortized over the life of the contracts. The financial results of EMAC prior to the date of acquisition were not material to our results of operations, therefore, pro forma information has not been provided.
Unaudited Pro Forma Information
The following table presents unaudited pro forma consolidated revenues, net income and net income per limited partner unit as if the Legacy Inergy reverse acquisition and the Arrow Acquisition had been included in our consolidated results for the year ended December 31, 2012 and for the entire year ended December 31, 2013 (in millions, except per unit information). All other acquisitions were immaterial in consolidation.
	Year Ended December 31,
	2013		2012 (1)
Revenues	$	3,449.30	$	2,267.20
Net income	$	3.9	$	49.8
Net income per limited partner unit(2):
Basic	$	0.04	$	0.31
Diluted	$	0.04	$	0.29
-1	The year ended December 31, 2012 has also been adjusted to reflect the contribution of Inergy, L.P.'s retail operations to Suburban Propane Partners on August 1, 2012 and the subsequent distribution on September 14, 2012 of 99% of the Suburban Propane Partners LP units acquired in the contribution as if that contribution and subsequent distribution had been removed from the consolidated results of operations at the beginning of each period presented.
(2) Basic and diluted net income per limited partner unit for the year ended December 31, 2012 were computed based on the presumption that the common and subordinated units issued to acquire Legacy Crestwood GP (the accounting predecessor) were outstanding for the entire period prior to the June 19, 2013 acquisition.
These amounts have been calculated after applying our accounting policies and adjusting the results of the acquisitions to reflect the depreciation and amortization based on the estimated fair value adjustments to property, plant and equipment and intangible assets.

Certain_Balance_Sheet_Informat

Certain Balance Sheet Information	12 Months Ended
	Dec. 31, 2014
Balance Sheet Related Disclosures [Abstract]
Certain Balance Sheet Information	Certain Balance Sheet Information
	Inventory
	Inventory consisted of the following at December 31, 2014 and 2013 (in millions):
		December 31,
		2014		2013
	NGLs	$	37.5	$	66.9
	Parts, supplies and other	9.1		6.7
	Total inventory	$	46.6	$	73.6
	Property, Plant and Equipment
	Property, plant and equipment consisted of the following at December 31, 2014 and 2013 (in millions):
		December 31,
		2014		2013
	Gathering systems and pipelines	$	1,410.90	$	1,473.40
	Facilities and equipment	1,648.30		1,186.50
	Buildings, land, rights-of-way, storage contracts and easements	841.5		814.7
	Vehicles	45.2		35.8
	Construction in process	156.5		365.8
	Base gas	37.5		102
	Salt deposits	120.5		120.5
	Office furniture and fixtures	13.5		10
		4,273.90		4,108.70
	Less: accumulated depreciation and depletion	380.1		203.4
	Total property, plant and equipment, net	$	3,893.80	$	3,905.30
	Depreciation. Depreciation expense totaled $184.2 million, $109.9 million and $49.1 million for the years ended December 31, 2014, 2013 and 2012. Depletion expense totaled $0.7 million and $0.4 million for the years ended December 31, 2014 and 2013. Legacy Crestwood GP did not have depletion expense.
	Capitalized Interest. During the year ended December 31, 2014, 2013 and 2012 we capitalized interest of $7.7 million, $3.4 million and $0.2 million related to certain expansion projects.
	Capital Leases. We have a treating facility and certain auto leases which are accounted for as capital leases. Our treating facility lease is reflected in facilities and equipment in the above table. We had capital lease assets of $5.3 million and $5.0 million included in property, plant and equipment, net at December 31, 2014 and 2013.
	Sale of Long-Lived Assets. In July 2013, Legacy Crestwood sold a cryogenic plant and associated equipment for approximately $11.0 million (net of fees) and recognized a gain of approximately $4.4 million for the year ended December 31, 2013.
	Intangible Assets
	Intangible assets consisted of the following at December 31, 2014 and 2013 (in millions):
		December 31,
		2014		2013
	Customer accounts	$	583.7	$	576.9
	Covenants not to compete	9.6		7
	Gas gathering, compression and processing contracts	730.2		750.2
	Acquired storage contracts	29		43.5
	Trademarks	32.2		33.5
	Deferred financing costs	57.2		55.3
		1,441.90		1,466.40
	Less: accumulated amortization	210.6		106
	Total intangible assets, net	$	1,231.30	$	1,360.40
	The following table summarizes the total of accumulated amortization of intangible assets by the type of intangible asset at December 31, 2014 and 2013:
		December 31,
		2014		2013
	Customer accounts	$	72.5	$	18.7
	Covenants not to compete	3.2		1
	Gas gathering, compression and processing contracts	98		67.3
	Acquired storage contracts	12.7		8.6
	Trademarks	6.7		2.3
	Deferred financing costs	17.5		8.1
	Total accumulated amortization	$	210.6	$	106
	Amortization and interest expense for the years ended December 31, 2014, 2013 and 2012, was approximately $109.8 million, $66.7 million and $28.9 million.
	Estimated amortization of our intangible assets for the next five years is as follows (in millions):
	Year Ending
	December 31,
	2015	$	115.1
	2016	101.2
	2017	87.5
	2018	73.9
	2019	65.5
	Accrued Expenses and Other Liabilities
	Accrued expenses and other liabilities consisted of the following at December 31, 2014 and 2013 (in millions):
		December 31,
		2014		2013
	Accrued expenses	$	52.5	$	40.3
Accrued property taxes	2.2		9.4
Accrued product purchases payable	0.7		1.6
Tax payable	1.6		14.8
Interest payable	23.5		16.7
Accrued additions to property, plant and equipment	20		58.2
Commitments and contingent liabilities (Note 15)	40		31.4
Capital leases	1.9		2.6
Deferred revenue	12.2		2.1
Total accrued expenses and other liabilities	$	154.6	$	177.1

Asset_Retirement_Obligations

Asset Retirement Obligations	12 Months Ended
	Dec. 31, 2014
Asset Retirement Obligation Disclosure [Abstract]
Asset Retirement Obligation	Asset Retirement Obligations
	We have legal obligations associated with right-of-way contracts we hold and at our facilities whether owned or leased. Where we can reasonably estimate the asset retirement obligation, we accrue a liability based on an estimate of the timing and amount of settlement. We record changes in these estimates based on changes in the expected amount and timing of payments to settle our obligations.
	The following table presents the changes in the net asset retirement obligations for the years ended December 31, 2014 and 2013 (in millions):
		December 31,
		2014		2013
	Net asset retirement obligation at January 1	$	15.1	$	14
	Liabilities incurred	4.6		—
	Acquisitions	1.2		—
	Accretion expense	1.1		0.8
	Changes in estimate	1.8		0.3
	Net asset retirement obligation at December 31	$	23.8	$	15.1
	We did not have any material assets that were legally restricted for use in settling asset retirement obligations as of December 31, 2014 and 2013.

Investments_in_Unconsolidated_

Investments in Unconsolidated Affiliates	12 Months Ended
	Dec. 31, 2014
Equity Method Investments and Joint Ventures [Abstract]
Investments in Unconsolidated Affiliates	Investments in Unconsolidated Affiliates
	Jackalope Gas Gathering Services, L.L.C.
	Crestwood Niobrara LLC (Crestwood Niobrara), our consolidated subsidiary, owns a 50% ownership interest in Jackalope Gas Gathering Services, L.L.C. (Jackalope). Williams Partners LP operates and owns the remaining 50% interest in Jackalope. Crestwood Niobrara manages the commercial operations of the Jackalope system, and we account for our investment in Jackalope under the equity method of accounting. Our Jackalope investment is included in our gathering and processing segment.
	In July 2013, Crestwood Niobrara acquired its interest in Jackalope from RKI Exploration and Production, LLC (RKI), an affiliate of Crestwood Holdings, for approximately $107.5 million. During the years ended December 31, 2014 and 2013, Crestwood Niobrara contributed $105.2 million and $19.6 million to Jackalope to fund the construction of its gathering and processing system.
	Our investment in Jackalope was $232.9 million and $127.2 million at December 31, 2014 and 2013. We have reflected the earnings from our investment in Jackalope in our consolidated statements of operations, which includes our share of Jackalope’s net earnings based on our ownership interest and other adjustments recorded by us as discussed below. Our share of Jackalope’s net earnings was approximately $3.6 million and $1.5 million for the years ended December 31, 2014 and 2013. As of December 31, 2014, our investment balance in Jackalope exceeded our equity in the underlying net assets of Jackalope by approximately $53.7 million. We amortize and generally assess the recoverability of this amount over 20 years, which represents the life of Jackalope’s gathering agreement with Chesapeake Energy Corporation (Chesapeake) and RKI . The amortization is reflected as a reduction of our earnings from unconsolidated affiliates, and we recorded amortization expense of approximately $3.1 million and $1.4 million for the years ended December 31, 2014 and 2013.
	Jackalope is required to make quarterly distributions of its available cash to its members based on their respective ownership percentage. During the years ended December 31, 2014 and 2013, Jackalope did not make any distributions to its members.
	We entered into a construction agreement with Jackalope, pursuant to which we assumed the responsibility to construct a truck terminal and storage facility. Under this agreement, Jackalope reimburses us for all costs incurred on its behalf, therefore, no revenues are recognized under this agreement.
	Tres Palacios Holdings LLC
	In December 2014, we sold our 100% interest in Tres Palacios to Tres Holdings, a newly formed joint venture between Crestwood Midstream's consolidated subsidiary and an affiliate of Brookfield Infrastructure Group (Brookfield), for total cash consideration of approximately $132.8 million, of which $66.4 million was paid by Crestwood Midstream. As a result of this transaction, effective December 1, 2014, we deconsolidated the operations of Tres Palacios. Crestwood Midstream owns 50.01% of Tres Holdings and is the operator of Tres Palacios and its assets. Brookfield owns the remaining 49.99% interest in Tres Holdings. Crestwood Midstream accounts for its investment in Tres Holdings under the equity method of accounting, and the investment is included in our storage and transportation segment.
	The sale of our 100% interest in Tres Palacios was accounted for under the accounting standards related to in substance real estate transactions. The accounting for the sale of real estate results in the recognition of a gain to the extent the sale is to an independent buyer. Since we retained 50.01% of our interest in Tres Palacios through our ownership in Crestwood Midstream, we recognized only the portion of the gain related to sale to Brookfield of approximately $30.6 million and, as a result, no gain was recognized on the portion of the sale between Crestwood Midstream and us. The sale of our interest in Tres Palacios to Crestwood Midstream was considered a transaction between entities under common control and, as a result, Crestwood Midstream reflected its investment at approximately $35.8 million, which represented 50.01% of our historical basis in Tres Palacios .
	Tres Palacios is a 38.4 Bcf multi-cycle, salt dome storage facility. Its 60-mile, dual 24-inch diameter header system (including a 51-mile north pipeline lateral and an approximate 11-mile south pipeline lateral) interconnects with 10 pipeline systems and can receive residue gas from the tailgate of Kinder Morgan Inc.'s Houston central processing plant.
	Crestwood Midstream’s investment in Tres Holdings was $36.0 million at December 31, 2014. We have reflected the earnings from our investment in Tres Holdings in our consolidated statements of operations, which includes our share of Tres Holdings' net earnings based on our ownership interest and other adjustments recorded by us as discussed below. Our share of Tres Holdings' net earnings was approximately $0.1 million for the year ended December 31, 2014. As of December 31, 2014, our equity in the underlying net assets exceeded our investment balance in Tres Holdings by approximately $30.6 million. We amortize and generally assess the recoverability of this amount over the life of the property, plant and equipment of Tres Palacios. The amortization is reflected as an increase in our earnings from unconsolidated affiliates, and we recorded amortization of approximately $0.1 million for the year ended December 31, 2014.
	Tres Holdings is required, within 30 days following the end of each quarter, to make quarterly distributions of its available cash (as defined in its limited liability company agreement) to its members based on their respective ownership percentage. Tres Holdings' distribution requirement to its members commences with the quarter ended March 31, 2015.
	A consolidated subsidiary of Crestwood Midstream entered into an operating agreement with Tres Palacios, pursuant to which we assumed the responsibility of operating and maintaining the facilities as well as certain administrative and other general services identified in the agreement. Under the operating agreement, Tres Palacios reimburses us for all cost incurred on its behalf. Crestwood Midstream did not receive any reimbursements under this agreement during the year ended December 31, 2014. In addition to our operating agreement, Crestwood Equity also entered into an indemnification agreement with Tres Palacios to indemnify Tres Palacios for property tax liabilities associated with periods prior to the sale. Pursuant to the indemnification agreement, any property tax refunds received by Tres Palacios will be payable to Crestwood Equity.
	Powder River Basin Industrial Complex, LLC
	Crestwood Crude Logistics LLC (Crude Logistics), our consolidated subsidiary, owns a 50% ownership interest in Powder River Basin Industrial Complex, LLC (PRBIC) which we account for under the equity method of accounting. Our PRBIC investment is included in our NGL and crude services segment.
	In September 2013, Crude Logistics and Enserco Midstream, LLC formed PRBIC to construct, own and operate and early stage crude oil terminal located in Douglas County, Wyoming. The terminal was placed in manifest service in August 2013. Crude Logistics paid approximately $22.5 million to acquire its interest in PRBIC. During the years ended December 31, 2014 and 2013, Crude Logistics contributed approximately $3.4 million and $1.9 million to PRBIC to fund its construction projects.
	Our investment in PRBIC was $26.2 million and $24.2 million at December 31, 2014 and 2013. During the years ended December 31, 2014 and 2013, our share of PRBIC’s loss was approximately $1.4 million and $0.2 million. As of December 31, 2014 and 2013, our investment balance in PRBIC approximated our equity in the underlying net assets of PRBIC.
	PRBIC is required to make quarterly distributions of its available cash to its members based on their respective ownership percentage. During the years ended December 31, 2014 and 2013, PRBIC did not make any distributions to its members. In February 2015, we received a cash distribution of approximately $0.3 million from PRBIC.

Risk_Management

Risk Management	12 Months Ended
	Dec. 31, 2014
Risk Management - Notional Amounts and Terms of Companys Derivative Financial Instruments [Abstract]
Risk Management	Risk Management
	We are exposed to certain market risks related to our ongoing business operations. These risks include exposure to changing commodity prices as well as fluctuations in interest rates. We utilize derivative instruments to manage our exposure to fluctuations in commodity prices, which is discussed below. We also periodically utilize derivative instruments to manage our exposure to fluctuations in interest rates, which is discussed in Note 9. Additional information related to our derivatives is discussed in Note 2 and Note 8.
	Commodity Derivative Instruments and Price Risk Management
	Risk Management Activities
	We sell NGLs to energy related businesses and may use a variety of financial and other instruments including forward contracts involving physical delivery of NGLs, heating oil and crude oil. We will periodically enter into offsetting positions to economically hedge against the exposure our customer contracts create. Certain of these contracts and positions are derivative instruments. We do not designate any of our commodity-based derivatives as hedging instruments for accounting purposes. Our commodity-based derivatives are reflected at fair value in the consolidated balance sheets, and changes in the fair value of these derivatives that impact the consolidated statements of operations are reflected in costs of product/services sold. During the years ended December 31, 2014 and 2013, the impact to the statement of operations related to our commodity-based derivatives reflected in costs of product/services sold was a gain of $51.2 million and a loss of $11.2 million. We attempt to balance our contractual portfolio in terms of notional amounts and timing of performance and delivery obligations. This balance in the contractual portfolio significantly reduces the volatility in costs of product/services sold related to these instruments. There were no risk management activities at December 31, 2012.
	Commodity Price and Credit Risk
	Notional Amounts and Terms
	The notional amounts and terms of our derivative financial instruments include the following at December 31, 2014 and 2013(in millions):
		31-Dec-14		31-Dec-13
		Fixed Price	Fixed Price	Fixed Price	Fixed Price
		Payor	Receiver	Payor	Receiver
	Propane, crude and heating oil (barrels)	6.8	8.4	5.6	6.8
	Natural gas (MMBTU’s)	0.2	0.1	—	—
	Notional amounts reflect the volume of transactions, but do not represent the amounts exchanged by the parties to the financial instruments. Accordingly, notional amounts do not reflect our monetary exposure to market or credit risks.
	All contracts subject to price risk had a maturity of 35 months or less; however, 95% of the contracts expire within 12 months.
	Credit Risk
	Inherent in our contractual portfolio are certain credit risks. Credit risk is the risk of loss from nonperformance by suppliers, customers or financial counterparties to a contract. We take an active role in managing credit risk and have established control procedures, which are reviewed on an ongoing basis. We attempt to minimize credit risk exposure through credit policies and periodic monitoring procedures as well as through customer deposits, letters of credit and entering into netting agreements that allow for offsetting counterparty receivable and payable balances for certain financial transactions, as deemed appropriate. The counterparties associated with our assets from price risk management activities as of December 31, 2014 and 2013 were energy marketers and propane retailers, resellers and dealers.
	Certain of our derivative instruments have credit limits that require us to post collateral. The amount of collateral required to be posted is a function of the net liability position of the derivative as well as our established credit limit with the respective counterparty. If our credit rating were to change, the counterparties could require us to post additional collateral. The amount of additional collateral that would be required to be posted would vary depending on the extent of change in our credit rating as well as the requirements of the individual counterparty. The aggregate fair value of all commodity derivative instruments with credit-risk-related contingent features that were in a liability position at December 31, 2014 and 2013, was $5.2 million and $16.6 million for which we had posted $1.8 million and $2.6 million of collateral in the normal course of business. In addition, at December 31, 2014 and 2013, we posted $5.0 million and $3.6 million of NYMEX margin deposits in the normal course of business. At December 31, 2014 and 2013, we also received collateral of $33.6 million and $5.9 million in the normal course of business. All collateral amounts have been netted against the asset or liability with the respective counterparty and is reflected in our consolidated balance sheets as assets and liability from price risk management activities.

Fair_Value_Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2014
Fair Value, Assets, Liabilities and Stockholders' Equity Measured on Recurring Basis [Abstract]
Fair Value Measurements	Fair Value Measurements
	The accounting standard for fair value measurement establishes a three-tier fair value hierarchy, which prioritizes the inputs used in measuring fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurement) and the lowest priority to unobservable inputs (Level 3 measurement). The three levels of the fair value hierarchy are as follows:
	•	Level 1—Quoted prices are available in active markets for identical assets or liabilities as of the reporting date. Active markets are those in which transactions for the asset or liability occur in sufficient frequency and volume to provide pricing information on an ongoing basis. Level 1 primarily consists of financial instruments such as exchange-traded derivatives, listed equities and US government treasury securities.
	•	Level 2—Pricing inputs are other than quoted prices in active markets included in Level 1, which are either directly or indirectly observable as of the reporting date. Level 2 includes those financial instruments that are valued using models or other valuation methodologies. These models are primarily industry-standard models that consider various assumptions, including quoted forward prices for commodities, time value, volatility factors, and current market and contractual prices for the underlying instruments, as well as other relevant economic measures. Substantially all of these assumptions are observable in the marketplace throughout the full term of the instrument, can be derived from observable data or are supported by observable levels at which transactions are executed in the marketplace. Instruments in this category include non-exchange-traded derivatives such as over the counter (OTC) forwards, options and physical exchanges.
	•	Level 3—Pricing inputs include significant inputs that are generally less observable from objective sources. These inputs may be used with internally developed methodologies that result in management’s best estimate of fair value.
	Cash, Accounts Receivable and Accounts Payable
	As of December 31, 2014 and 2013, the carrying amounts of cash, accounts receivable and accounts payable represent fair value based on their short-term nature of theses instruments.
	Credit Facilities
	The fair value of the amounts outstanding under our credit facilities approximates their carrying amounts as of December 31, 2014 and 2013, due primarily to the variable nature of the interest rates of the instruments, which is considered a Level 2 fair value measurement.
	Senior Notes
	We estimate the fair value of our senior notes primarily based on quoted market prices for the same or similar issuances (representing a Level 2 fair value measurement). The following table reflects the carrying value and fair value of the senior notes (in millions):
		December 31, 2014				December 31, 2013
		Carrying Amount		Fair		Carrying Amount		Fair
				Value				Value
	CEQP Senior Notes	$	11.4	$	11.6	$	11.4	$	11.6
	Crestwood Midstream 2019 Senior Notes	$	351	$	360.5	$	351.2	$	379.3
	Crestwood Midstream 2020 Senior Notes	$	504	$	481.6	$	504.7	$	513.8
	Crestwood Midstream 2022 Senior Notes	$	600	$	568.5	$	600	$	617.3
	Financial Assets and Liabilities
	As of December 31, 2014, we held certain financial assets and liabilities that are required to be measured at fair value on a recurring basis, which include our derivative instruments related to heating oil, crude oil, NGLs and interest rates. Our derivative instruments consist of forwards, swaps, futures, physical exchanges and options.
	Certain of our derivative instruments are traded on the NYMEX. These instruments have been categorized as Level 1.
	Our derivative instruments also include OTC contracts, which are not traded on a public exchange. The fair values of these derivative instruments are determined based on inputs that are readily available in public markets or can be derived from information available in publicly quoted markets. These instruments have been categorized as Level 2.
	Our OTC options are valued based on the Black Scholes option pricing model that considers time value and volatility of the underlying commodity. The inputs utilized in the model are based on publicly available information as well as broker quotes. These options have been categorized as Level 2.
	Our financial assets and liabilities are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. The assessment of the significance of a particular input to the fair value measurement requires judgment, and may affect the valuation of fair value assets and liabilities and their placement within the fair value hierarchy levels.
	The following tables set forth by level within the fair value hierarchy, our financial instruments that were accounted for at fair value on a recurring basis at December 31, 2014 and 2013 (in millions):
		31-Dec-14
		Fair Value of Derivatives
		Level 1		Level 2		Level 3		Total		Netting			Total
										Agreements(1)
	Assets
	Assets from price risk management	$	0.5	$	146.7	$	—	$	147.2	$	(67.4	)	$	79.8
	Suburban Propane Partners, L.P. units	6.1		—		—		6.1		—			6.1
	Total assets at fair value	$	6.6	$	146.7	$	—	$	153.3	$	(67.4	)	$	85.9
	Liabilities
	Liabilities from price risk management	$	1.6	$	99.2	$	—	$	100.8	$	(75.4	)	$	25.4
	Interest rate swaps	—		1.6		—		1.6		—			1.6
	Total liabilities at fair value	$	1.6	$	100.8	$	—	$	102.4	$	(75.4	)	$	27
		31-Dec-13
		Fair Value of Derivatives
		Level 1		Level 2		Level 3		Total		Netting			Total
										Agreements(1)
	Assets
	Assets from price risk management	$	0.3	$	27.7	$	—	$	28	$	(13.5	)	$	14.5
	Suburban Propane Partners, L.P. units	6.7		—		—		6.7		—			6.7
	Total assets at fair value	$	7	$	27.7	$	—	$	34.7	$	(13.5	)	$	21.2
	Liabilities
	Liabilities from price risk management	$	0.1	$	39.5	$	—	$	39.6	$	(4.7	)	$	34.9
	Interest rate swaps	—		4.3		—		4.3		—			4.3
	Total liabilities at fair value	$	0.1	$	43.8	$	—	$	43.9	$	(4.7	)	$	39.2
	(1) Amounts represent the impact of legally enforceable master netting agreements that allow us to settle positive and negative positions as well as cash collateral held or placed with the same counterparties.

LongTerm_Debt

Long-Term Debt	12 Months Ended
	Dec. 31, 2014
Text Block [Abstract]
Long-Term Debt	Long-Term Debt
	Long-term debt consisted of the following at December 31, 2014 and 2013, (in millions):
		December 31,		December 31,
		2014		2013
	CEQP Credit Facility	$	369	$	381
	CEQP Senior Notes	11.4		11.4
	Crestwood Midstream Revolver	555		414.9
	Crestwood Midstream 2019 Senior Notes	350		350
	Premium on Crestwood Midstream 2019 Senior Notes	1		1.2
	Crestwood Midstream 2020 Senior Notes	500		500
	Fair value adjustment of Crestwood Midstream 2020 Senior Notes	4		4.7
	Crestwood Midstream 2022 Senior Notes	600		600
	Other	6.1		2.8
	Total debt	2,396.50		2,266.00
	Less: current portion	3.7		5.1
	Total long-term debt	$	2,392.80	$	2,260.90
	Crestwood Equity and its subsidiaries do not provide credit support or guarantee any amounts outstanding under the credit facilities or notes of Crestwood Midstream. Crestwood Midstream and its subsidiaries do not provide credit support or guarantee any amounts outstanding under the Crestwood Equity credit facility or senior notes.
	CEQP Credit Facility
	Description of Credit Facility. We utilize a secured credit facility (the CEQP Credit Facility) with an aggregate revolving loan capacity of $495 million due July 2016, to fund working capital requirements, capital expenditures and acquisitions and for general partnership purposes. All borrowings under the CEQP Credit Facility are generally secured by substantially all of our assets and the equity interests in all of our wholly owned subsidiaries, and loans thereunder bear interest, at our option, subject to certain limitations, at a rate equal to the following:
	•	the Alternate Base Rate, which is defined as the higher of (i) the federal funds rate plus 0.50%; (ii) JP Morgan's prime rate; or (iii) Adjusted LIBOR plus 1%; plus a margin varying from 0.75% to 2.00%; or
	•	Adjusted LIBOR, which is defined as the LIBOR plus a margin varying from 1.75% to 3.00%.
	We are required to use 50% of the net cash proceeds (that are not applied to purchase replacement assets) from asset dispositions (other than the sale of inventory and motor vehicles in the ordinary course of business, sales of assets among us and our domestic subsidiaries and the sale or disposition of obsolete or worn equipment) to reduce borrowings under the CEQP Credit Facility during any fiscal year in which unapplied net cash proceeds are in excess of $50 million.
	In September 2014, we amended the CEQP Credit Facility, among other things, to (i) increase the general partnership commitment from $550 million to $625 million; (ii) decrease the expansion option from $100 million to $25 million; and (iii) modify the maximum total leverage ratio financial covenant levels as discussed further below. The fees paid to our bank syndicate for this amendment were approximately $1.7 million and we amortize such fees over the remaining term of the facility. In conjunction with the sale of our interest in Tres Palacios in December 2014, the CEQP Credit Facility commitment was reduced to $495 million from $625 million, and as a result of the reduction in capacity, we expensed approximately $0.5 million of debt issue costs.
	At December 31, 2014 and 2013, the balance outstanding under the CEQP Credit Facility was $369.0 million and $381.0 million and outstanding standby letters of credit were $56.7 million and $52.7 million. We had $69.3 million of available capacity under the revolving credit facility at December 31, 2014 considering our most restrictive debt covenants under the facility. The interest rates on the CEQP Credit Facility are based on prime rate and LIBOR plus the applicable spreads, resulting in interest rates which were between 2.91% and 5.00% at December 31, 2014 and 2.67% and 4.75% at December 31, 2013. The weighted-average interest rate as of December 31, 2014 and 2013 was 3.02% and 2.68%.
	Restrictive Covenants. The CEQP Credit Facility contains various covenants and restrictive provisions that limit its ability to, among other things, (i) incur additional debt; (ii) make distributions on or redeem or repurchase units; (iii) make certain investments and acquisitions; (iv) incur or permit certain liens to exist; (v) enter into certain types of transactions with affiliates; (vi) merge, consolidate or amalgamate with another company; and (vii) transfer or otherwise dispose of assets.
	The CEQP Credit Facility contains the following financial covenants:
	•	the ratio of our total funded debt (as defined in the credit agreement) to consolidated EBITDA (as defined in the credit agreement) was amended in September 2014 to increase the ratio from 4.75 to 1.0 to no greater than (i) 5.50 to 1.0 for the quarter ended December 31, 2014; (ii) 5.25 to 1.0 for the quarter ended March 31, 2015; (iii) 5.00 to 1.0 for the quarter ended June 30, 2015; and (iv) 4.75 to 1.0 for the quarter ended September 30, 2015 and all subsequent quarters.
	•	the ratio of our consolidated EBITDA to consolidated interest expense (as defined in the credit agreement), for the four quarters then most recently ended, must not be less than 2.50 to 1.0.
	At December 31, 2014, the total funded debt to consolidated EBITDA was approximately 3.87 to 1.0 and consolidated EBITDA to consolidated interest expense was approximately 8.32 to 1.0.
	If we fail to perform our obligations under these and other covenants, the CEQP Credit Facility could be terminated and any outstanding borrowings, together with accrued interest, under the credit agreement could be declared immediately due and payable. The credit agreement also has cross default provisions that apply to any other material indebtedness of ours, excluding the debt of Crestwood Midstream.
	Events of default under the credit agreement governing the CEQP Credit Facility include, among other things: default in payment of principal when due; default in payment of interest, fees or other amounts within three days of their due date; and violation of specified affirmative and negative covenants.
	At December 31, 2014, we were in compliance with the debt covenants in the CEQP Credit Facility.
	Interest Rate Swaps. We have entered into six interest rate swaps that mature in 2015 and 2016 to reduce our exposure to variable interest payments due under the CEQP Credit Facility. These swap agreements require us to pay the counterparty an amount based on fixed rates from 0.84% to 2.52% due quarterly on an aggregate notional amount of $225 million. In exchange, the counterparty is required to make quarterly floating interest rate payments on the same date to us based on the three-month LIBOR applied to the same aggregate notional amount of $225 million. During the year ended December 31, 2014, we recorded a gain of approximately $2.6 million associated with these interest rate swaps, which is reflected as a reduction of our interest and debt expense, net on our consolidated statements of operations. These interest rate swaps are not designated as hedges for accounting purposes.
	CEQP Senior Notes
	At December 31, 2014, we had $11.4 million in outstanding senior notes, the majority of which mature on October 1, 2018 and have a coupon rate of 7%. The outstanding senior notes do not contain any financial covenants.
	Crestwood Midstream Revolver
	Description of Facility. Crestwood Midstream has a five-year $1.0 billion senior secured revolving credit facility due in October 2018 (the Crestwood Midstream Revolver), which is available to fund acquisitions, working capital and internal growth projects and for general partnership purposes. The Crestwood Midstream Revolver includes a sub-limit up to $25 million for same-day swing line advances and a sub-limit up to $250 million for letters of credit. Subject to limited exception, the Crestwood Midstream Revolver is secured by substantially all of the equity interests and assets of Crestwood Midstream’s restricted domestic subsidiaries, and is joint and severally guaranteed by substantially all of its restricted domestic subsidiaries, except for Crestwood Niobrara LLC, Crestwood Crude Logistics LLC and CMLP Tres Manager LLC.
	In June 2014, Crestwood Midstream amended its revolver to clarify, among other things, (i) the methodology for calculating the value of its investment in certain joint ventures constituting unrestricted subsidiaries; and (ii) that redemptions, repurchases and retirements of equity interests are permitted to the extent made solely through the issuance of additional equity units. Crestwood Midstream did not pay any fees to its bank syndicate for this amendment.
	At December 31, 2014 and 2013, the balance outstanding on the Crestwood Midstream Revolver was $555.0 million and $414.9 million and outstanding standby letters of credit were $15.1 million and $30.7 million. Crestwood Midstream had $429.9 million of available capacity under its revolving credit facility at December 31, 2014 considering its most restrictive debt covenants under the facility. The interest rates on the Crestwood Midstream Revolver are based on the prime rate and LIBOR plus the applicable spreads, resulting in interest rates which were between 2.66% and 4.75% at December 31, 2014 and 2.67% and 4.75% at December 31, 2013. The weighted-average interest rate as of December 31, 2014 and 2013 was 2.86% and 2.75%.
	Borrowings under the Crestwood Midstream Revolver (other than swing line loans) bear interest at its option at either:
	•	the Alternate Base Rate, which is defined as the highest of (i) the federal funds rate plus 0.50%; (ii) JP Morgan's prime rate; or (iii) Adjusted LIBOR plus 1%; plus a margin varying from 0.75% to 1.75% depending on Crestwood Midstream's most recent total leverage ratio; or
	•	Adjusted LIBOR, which is defined as LIBOR plus a margin varying from 1.75% to 2.75% depending on Crestwood Midstream's most recent total leverage ratio.
	Swingline loans bear interest at the Alternate Base Rate plus a margin varying from 0.75% to 1.75%. The unused portion of the Crestwood Midstream Revolver is subject to a commitment fee ranging from 0.30% to 0.50% per annum according to Crestwood Midstream's most recent total leverage ratio. Interest on Alternative Base Rate loans is payable quarterly or, if Adjusted LIBOR applies, it may be paid at more frequent intervals.
	Restrictive Covenants. The Crestwood Midstream Revolver contains various covenants and restrictive provisions that limit Crestwood Midstream's ability to, among other things, (i) incur additional debt; (ii) make distributions on or redeem or repurchase units; (iii) make certain investments and acquisitions; (iv) incur or permit certain liens to exist; (v) enter into certain types of transactions with affiliates; (vi) merger, consolidate or amalgamate with another company; and (vii) transfer or otherwise dispose of assets.
	The Crestwood Midstream Revolver requires maintenance of a consolidated leverage ratio (as defined in its credit agreement) of not more than 5.00 to 1.0 (and, if applicable, 5.50 to 1.0 during certain periods immediately following a material acquisition by us) and an interest coverage ratio (as defined in its credit agreement) of not less than 2.50 to 1.0. At December 31, 2014, the net debt to consolidated EBITDA was approximately 4.50 to 1.0 and consolidated EBITDA to consolidated interest expense was approximately 3.99 to 1.0.
	In December 2014, Crestwood Midstream notified the administrative agent of its election to commence an Acquisition Period (as defined in our credit agreement) effective as of December 3, 2014. Crestwood Midstream made this election following its acquisition of a 50.01% indirect interest in Tres Palacios. Crestwood Midstream's consolidation leverage ratio (as defined in its credit agreement) increases to 5.50 to 1.0 during the 270-day Acquisition Period as a result of this election.
	If Crestwood Midstream fails to perform its obligations under these and other covenants, the lenders' credit commitment could be terminated and any outstanding borrowings, together with accrued interest, under the Crestwood Midstream Revolver could be declared immediately due and payable. The Crestwood Midstream Revolver also has cross default provisions that apply to any other material indebtedness of Crestwood Midstream.
	Crestwood Midstream Senior Notes
	2019 Senior Notes. In April 2011, Legacy Crestwood and Crestwood Midstream Finance Corporation (Legacy Crestwood Finance and together with Legacy Crestwood, the Legacy Crestwood Issuers) issued $200 million of 7.75% Senior Notes due 2019 (the Initial 2019 Senior Notes) in a private offering . On November 14, 2012, the Legacy Crestwood Issuers issued and sold an additional $150 million of these notes (the Additional 2019 Senior Notes, and together with the Initial 2019 Senior Notes, the 2019 Senior Notes). The 2019 Senior Notes will mature on April 1, 2019, and interest is payable semi-annually in arrears on April 1 and October 1 of each year.
	Following the close of the Crestwood Merger on October 7, 2013, (i) Crestwood Midstream and Crestwood Midstream Finance Corp. (Finance Corp) assumed the obligations of Legacy Crestwood and Legacy Crestwood Finance under their 2019 Senior Notes; (ii) certain Legacy Crestwood subsidiary guarantors of the 2019 Senior Notes guaranteed the obligations of Crestwood Midstream and Finance Corp. under the 2020 Senior Notes described below; (iii) Crestwood Midstream’s subsidiary guarantors of the 2020 Senior Notes guaranteed the obligations of the Legacy Crestwood Issuers under the 2019 Senior Notes; and (iv) Legacy Crestwood Finance merged with and into NRGM Finance Corp., with NRGM Finance Corp. continuing as the surviving entity and immediately thereafter changing its name to Crestwood Midstream Finance Corp.
	2020 Senior Notes. At December 31, 2014, the balance outstanding on Crestwood Midstream's 6.0% Senior Notes due 2020 (the 2020 Senior Notes) was $500 million. We recorded an adjustment in conjunction with Legacy Crestwood GP's reverse acquisition of us to adjust the debt to fair value. At the December 31, 2014 and 2013, the unamortized balance of the adjustment was $4.0 million and $4.7 million. The adjustment is being amortized over the remaining life of the 2020 Senior Notes. The senior notes will mature on December 15, 2020, and interest is payable semi-annually in arrears on June 15 and December 15 of each year.
	2022 Senior Notes. In November 2013, Crestwood Midstream and Finance Corp, completed an offering of $600 million in aggregate principal amount of 6.125% Senior Notes due 2022 (the 2022 Senior Notes) in a private offering exempt from registration requirements of the Securities Act of 1933. Crestwood Midstream used the net proceeds from the offering to fund a portion of the consideration paid in the Arrow Acquisition and related fees and expenses, and to repay borrowings under the Crestwood Midstream Revolver.
	On July 17, 2014, Crestwood Midstream filed a registration statement with the SEC under which it offered to exchange the 2022 Senior Notes for any and all outstanding 2022 Senior Notes, which were issued in the private offering in November 2013. Crestwood Midstream completed the exchange offer on August 29, 2014. The terms of the exchange notes are substantially identical to the terms of the 2022 Senior Notes, except that the exchange notes are freely tradable.  At December 31, 2014, the balance outstanding on the 2022 Senior Notes was $600 million.
	In general, each series of Crestwood Midstream's senior notes are fully and unconditionally guaranteed, joint and severally, on a senior unsecured basis by Crestwood Midstream’s domestic restricted subsidiaries (other than Finance Corp). The indentures contain customary release provisions, such as (i) disposition of all or substantially all the assets of, or the capital stock of, a guarantor subsidiary to a third person if the disposition complies with the indentures; (ii) designation of a guarantor subsidiary as an unrestricted subsidiary in accordance with its indentures; (iii) legal or covenant defeasance of a series of senior notes, or satisfaction and discharge of the related indenture; and (iv) guarantor subsidiary ceases to guarantee any other indebtedness of Crestwood Midstream or any other guarantor subsidiary, provided it no longer guarantees indebtedness under the Crestwood Midstream Revolver.
	The indentures restricts the ability of Crestwood Midstream and its restricted subsidiaries to, among other things, sell assets; redeem or repurchase subordinated debt; make investments; incur or guarantee additional indebtedness or issue preferred units; create or incur certain liens; enter into agreements that restrict distributions or other payments to Crestwood Midstream from its restricted subsidiaries; consolidate, merge or transfer all or substantially all of their assets; engage in affiliate transactions; and create unrestricted subsidiaries. These restrictions are subject to a number of exceptions and qualifications, and many of these restrictions will terminate when the senior notes are rated investment grade by either Moody's Investors Service, Inc. or Standard & Poor's Rating Services and no default or event of default (each as defined in the respective indentures) under the indentures has occurred and is continuing. In addition, under the indenture governing the Crestwood Midstream 2019 Senior Notes, Crestwood Midstream may not pay any dividend on its common units unless, among other things, at the time of and after giving effect to such dividend payment, no default under the indenture has occurred and is continuing or would occur as a consequence of such dividend payment.
	At December 31, 2014, Crestwood Midstream was in compliance with the debt covenants and restrictions in each of its credit agreements and discussed above.
	Notes Payable and Other Obligations
	Non-interest bearing obligations due under noncompetition agreements and other note payable agreements consisted of agreements between Legacy Inergy and the sellers of certain companies acquired from 2003 through 2014 with payments due through 2022 and imputed interest ranging from 5.02% to 8.00%. Non-interest bearing obligations consisted of $7.4 million in total payments due under agreements, less unamortized discount based on imputed interest of $1.3 million at December 31, 2014.
	Maturities
	The aggregate maturities of principal amounts on our outstanding long-term debt and other notes payable as of December 31, 2014 for the next five years and in total thereafter are as follows (in millions):
	2015	$	3.7
	2016	367.9
	2017	0.9
	2018	566.1
2019	350.9
Thereafter	1,102.00
Total debt	$	2,391.50
Residual Value Guarantee
In August 2012, we entered into a support agreement with Suburban Propane Partners, L.P. (SPH) pursuant to which we are obligated to provide contingent, residual support of approximately $497 million of aggregate principal amount of the 7.5% senior unsecured notes due 2018 of SPH and Suburban Energy Finance Corp. (collectively, the SPH Issuers) or any permitted refinancing thereof. Under the support agreement, in the event the SPH Issuers fail to pay any principal amount of the supported debt when due, we will pay directly to, or to the SPH Issuers for the benefit of, the holders of the supported debt an amount up to the principal amount of the supported debt that the SPH Issuers have failed to pay. We have no obligation to make a payment under the support agreement with respect to any accrued and unpaid interest or any redemption premium or other costs, fees, expenses, penalties, charges or other amounts of any kind that shall be due to noteholders by the SPH Issuers, whether on or related to the supported debt or otherwise. The support agreement terminates on the earlier of the date the supported debt is extinguished or on the maturity date of supported debt or any permitted refinancing thereof. We believe the probability of any future payment on this residual value guarantee is remote.

Earnings_Per_Limited_Partner_U

Earnings Per Limited Partner Unit	12 Months Ended
	Dec. 31, 2014
Earnings Per Share [Abstract]
Earnings Per Limited Partner Unit	Earnings Per Limited Partner Unit
	Our net income (loss) attributable to Crestwood Equity Partners is allocated to the subordinated and limited partner unitholders based on their ownership percentage. We calculate basic net income per limited partner unit by utilizing the two class method. Diluted net income per limited partner unit is computed by dividing net income attributable to the limited partners by the weighted-average number of units outstanding and the effect of dilutive units outstanding. The weighted average number of units outstanding is calculated based on the presumption that the common and subordinated units issued to acquire Legacy Crestwood GP (the accounting predecessor) were outstanding for the entire period prior to the June 19, 2013 acquisition. There were no units excluded from our dilutive earnings per share as we did not have any anti-dilutive units for the years ended December 31, 2014, 2013 and 2012.

Income_Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes
	The provision for income taxes for the years ended December 31, 2014, 2013, and 2012 consisted of the following (in millions):
		Year Ended December 31,
		2014			2013			2012
	Current:
	Federal	$	5		$	2.5		$	—
	State	1.3			1.3			1.2
	Total current	6.3			3.8			1.2
	Deferred:
	Federal	(5.3		)	(2.5		)	—
	State	0.1			(0.3		)	—
	Total deferred	(5.2		)	(2.8		)	—
	Provision for income taxes	$	1.1		$	1		$	1.2
	The effective rate differs from the statutory rate for the years ended December 31, 2014 and 2013, primarily due to the Partnership not being treated as a corporation for federal income tax purposes as discussed in Note 2.
	Deferred income taxes related to our wholly owned subsidiary, IPCH Acquisition Corp., and our Texas Margin tax reflect the net tax effects of temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes. Components of the deferred income taxes at December 31, 2014 and 2013 are as follows (in millions).
		December 31,
		2014			2013
	Deferred tax liability:
	Basis difference in stock of acquired company	$	(12.0	)	$	(17.2	)
	Total deferred tax liability	$	(12.0	)	$	(17.2	)
	Uncertain Tax Positions. We evaluate the uncertainty in tax positions taken or expected to be taken in the course of preparing our consolidated financial statements to determine whether the tax positions are more likely than not of being sustained by the applicable tax authority. Tax positions with respect to tax at the partnership level deemed not to meet the more likely than not threshold would be recorded as a tax benefit or expense in the current year. We believe that there were no uncertain tax positions that would impact our operations for the years ended December 31, 2014, 2013 and 2012 and that no provision for income tax was required for these consolidated financial statements. However, our conclusions regarding the evaluation are subject to review and may change based on factors including, but not limited to, ongoing analyses of tax laws, regulations and interpretations thereof.

Partners_Capital

Partners' Capital	12 Months Ended
	Dec. 31, 2014
Partners' Capital [Abstract]
Partners' Capital	Partners’ Capital
	Unit Issuances
	We periodically sell common units in public offerings to generate funds to reduce our indebtedness under our credit facilities and to fund acquisitions. The table below presents limited partner unit issuances by Legacy Crestwood, Inergy Midstream and Crestwood Midstream.
	Issuer		Issuance Date		Units			Per Unit				Per Unit		Net
								Gross Price				Net Price (1)		Proceeds
	Legacy Crestwood		January 13, 2012		3,500,000			$	30.73			$	29.5	$	103.1
	Legacy Crestwood		July 25, 2012		4,600,000		(2)	26				24.97		114.4
	Legacy Crestwood		March 22, 2013		5,175,000		(3)	23.9				23		118.5
	Inergy Midstream		September 13, 2013		11,773,191		(4)	22.5				21.69		255.2
	Crestwood Midstream		October 23, 2013		16,100,000		(5)	N/A				21.19		340.3
	(1)	Price is net of underwriting discounts.
	(2)	Includes 600,000 units that were issued in August 2012.
	(3)	Includes 675,000 units that were issued in April 2013.
	(4)	Includes 773,191 units that were issued on October 7, 2013.
	(5)	Includes 2,100,000 units that were issued on October 30, 2013.
	During 2011 and 2013, Legacy Crestwood issued Class C and Class D units, respectively, representing limited partner units. Legacy Crestwood had the option to pay distributions to its Class C and Class D unitholders with cash or by issuing additional paid-in-kind units based upon the volume common unit weighted-average price for 10 trading days immediately preceding the date the distribution was declared. On April 1, 2013, the outstanding Legacy Crestwood Class C units converted to common units on a one-for-one basis. In conjunction with the Crestwood Merger, Legacy Crestwood unitholders received 1.07 units of Legacy Inergy units for each unit of Legacy Crestwood they owned and as a result, there were no common or Class D units outstanding immediately following the Crestwood Merger. During 2013, Legacy Crestwood issued 183,995 and 292,660 additional Class C and Class D units in lieu of paying a quarterly cash distribution. For the year ended December 31, 2012, Legacy Crestwood issued 633,084 additional Class C units in lieu of paying quarterly cash distributions.
	Contributions
	During 2012, Legacy Crestwood's general partner made additional capital contributions of approximately $5.9 million in exchange for the issuance of an additional 215,722 general partner units.
	Distributions
	We make quarterly distributions to our partners within approximately 45 days after the end of each quarter in an aggregate amount equal to our available cash for such quarter. Available cash generally means, with respect to each quarter, all cash on hand at the end of the quarter less the amount of cash that the general partner determines in its reasonable discretion is necessary or appropriate to:
	•	provide for the proper conduct of our business;
	•	comply with applicable law, any of our debt instruments, or other agreements; or
	•	provide funds for distributions to unitholders for any one or more of the next four quarters;
	plus all cash on hand on the date of determination of available cash for the quarter resulting from working capital borrowings made after the end of the quarter. Working capital borrowings are generally borrowings that are made under our working capital facility and in all cases are used solely for working capital purposes or to pay distributions to partners. The amount of cash we have available for distribution depends primarily upon our cash flow (which consists of the cash distributions we receive in connection with our ownership of 100% of Crestwood Midstream's IDRs and 4% of Crestwood Midstream's common units) and the cash flow generated by certain of our consolidated subsidiaries not owned by Crestwood Midstream.
	Distributions to Partners
	During the years ended December 31, 2013 and 2012, Legacy Crestwood GP paid cash distributions to its member of $9.3 million and $13.8 million. In addition, during the year ended December 31, 2013, we paid cash distributions of approximately $11.8 million related to units that vested as a result of the Crestwood Merger discussed below.
	A summary of our limited partner quarterly cash distributions for the years ended December 31, 2014 and 2013 (subsequent to the June 19, 2013 reverse acquisition) is presented below:
	Record Date		Payment Date		Per Unit Rate				Cash Distributions
									(in millions)
	2014
	February 7, 2014		February 14, 2014		$	0.1375			$	25.6
	May 8, 2014		May 15, 2014		$	0.1375			25.7
	August 7, 2014		August 14, 2014		$	0.1375			25.6
	November 7, 2014		November 14, 2014		$	0.1375			25.6
									$	102.5
	2013
	August 7, 2013		August 14, 2013		$	0.13			$	22.3
	November 7, 2013		November 14, 2013		$	0.135			25
									$	47.3
	On February 13, 2015, we paid a distribution of $0.1375 per limited partner unit to unitholders of record on February 6, 2015 with respect to the fourth quarter of 2014.
	Non-Controlling Partners Equity
	Crestwood Midstream Class A Preferred Units
	On June 17, 2014, Crestwood Midstream entered into definitive agreements with a group of investors, including Magnetar Financial, affiliates of GSO Capital Partners LP and GE Energy Financial Services (the Class A Purchasers). Under these agreements, Crestwood Midstream has agreed to sell to the Class A Purchasers and the Class A Purchasers have agreed to purchase from Crestwood Midstream up to $500 million of Preferred Units at a fixed price of $25.10 per unit on or before September 30, 2015. During the year ended December 31, 2014, the Class A Purchasers purchased 17,529,879 Preferred Units for a cash purchase price of $25.10 per unit resulting in gross proceeds of approximately $440.0 million (net proceeds of approximately $430.5 million after deducting transaction fees and offering expenses). The Preferred Units are reflected as non-controlling interests in our consolidated financial statements.
	Subject to certain conditions, holders of the Preferred Units will have the right to convert Preferred Units into (i) common units on a one-for-one basis after June 17, 2017, or (ii) a number of common units determined pursuant to a conversion ratio set forth in the Crestwood Midstream partnership agreement upon the occurrence of certain events, such as a change in control. Also, subject to certain conditions after the full $500 million purchase commitment has been satisfied, Crestwood Midstream may convert the Preferred Units into common units at a conversion ratio set forth in the partnership agreement, which is based in part on the aggregate principal amount of the Preferred Units outstanding and the weighted average trading price of its common units.
	The Preferred Units have voting rights that are identical to the voting rights of the Crestwood Midstream common units and will vote with the common units as a single class, with each Preferred Unit entitled to one vote for each common unit into which such Preferred Unit is convertible, except that the Preferred Units are entitled to vote as a separate class on any matter on which all unitholders are entitled to vote that adversely affects the rights, powers, privileges or preferences of the Preferred Units in relation to Crestwood Midstream's other securities outstanding.
	On July 9, 2014, Crestwood Midstream filed a shelf registration statement with the SEC under which holders of the Preferred Units may sell the common units into which the Preferred Units are convertible. The registration statement became effective on July 18, 2014. Crestwood Midstream registered 26,299,076 common units under the registration statement.
	Crestwood Niobrara Preferred Interest
	Crestwood Niobrara issued a preferred interest to a subsidiary of General Electric Capital Corporation and GE Structured Finance, Inc. (collectively, GE) in conjunction with the acquisition of its investment in Jackalope. The preferred interest is reflected as non-controlling interest in our consolidated financial statements.
	Pursuant to Crestwood Niobrara's agreement with GE, GE made capital contributions to Crestwood Niobrara in exchange for an equivalent number of preferred units. During the years ended December 31, 2014 and 2013, GE made capital contributions of $53.9 million and $96.1 million to Crestwood Niobrara. As of December 31, 2014, GE has fulfilled its capital contribution commitment to Crestwood Niobrara of $150.0 million and is no longer required to make quarterly contributions to Crestwood Niobrara.
	Net Income (Loss) Attributable to Non-Controlling Partners
	The components of net income (loss) attributable to non-controlling partners on our consolidated statements of operations for the years ended December 31, 2014, 2013 and 2012 are as follows (in millions):
		Year Ended December 31,
		2014				2013				2012
	Crestwood Midstream limited partner interests	$	(100.8	)		$	(62.2	)		$	9.5
	Crestwood Niobrara preferred interests	16.8				4.9				—
	Crestwood Midstream Class A preferred units	17.2				—				—
	Net income (loss) attributable to non-controlling partners	$	(66.8	)		$	(57.3	)		$	9.5
	Distributions to Non-Controlling Partners
	Crestwood Midstream Limited Partners. Crestwood Midstream paid cash distributions to its limited partners (excluding distributions to its general partner and distributions paid in conjunction with the Crestwood Merger as discussed below) of $296.5 million and $179.6 million during the year ended December 31, 2014 and 2013. Legacy Crestwood paid cash distributions to its common unitholders of $89.7 million for the year ended December 31, 2012.
	The Crestwood Midstream partnership agreement requires them to distribute, within 45 days after the end of each quarter, all available cash (as defined in its partnership agreement) to unitholders of record on the applicable record date. We are not entitled to distributions on our non-economic general partner interest in Crestwood Midstream.
	Crestwood Midstream Class A Preferred Unitholders. Crestwood Midstream's partnership agreement requires it to make quarterly distributions to its Class A Preferred Unit holders. The holders of the Class A Preferred Units (the Preferred Units) are entitled to receive fixed quarterly distributions of $0.5804 per unit. For the 12 quarters following the quarter ended June 30, 2014 (the Initial Distribution Period), distributions on the Preferred Units can be made in additional Preferred Units, cash, or a combination thereof, at Crestwood Midstream's election. If Crestwood Midstream elects to pay the quarterly distribution through the issuance of additional Preferred Units, the number of units to be distributed will be calculated as the fixed quarterly distribution of $0.5804 per unit divided by the cash purchase price of $25.10 per unit. Crestwood Midstream accrues the fair value of such distribution at the end of the quarterly period and adjusts the fair value of the distribution on the date the additional Preferred Units are distributed. Distributions on the Preferred Units following the Initial Distribution Period will be made in cash unless, subject to certain exceptions, (i) there is no distribution being paid on Crestwood Midstream's common units and (ii) its available cash (as defined in its partnership agreement) is insufficient to make a cash distribution to its Preferred Unit holders. If Crestwood Midstream fails to pay the full amount payable to its Preferred Unit holders in cash following the Initial Distribution Period, then (x) the fixed quarterly distribution on the Preferred Units will increase to $0.7059 per unit, and (y) Crestwood Midstream will not be permitted to declare or make any distributions to its common unitholders until such time as all accrued and unpaid distributions on the Preferred Units have been paid in full in cash. In addition, if Crestwood Midstream fails to pay in full any Class A Preferred Distribution (as defined in its partnership agreement), the amount of such unpaid distribution will accrue and accumulate from the last day of the quarter for which such distribution is due until paid in full, and any accrued and unpaid distributions will be increased at a rate of 2.8125% per quarter. For additional information on the Preferred Units, see the Crestwood Midstream Class A Preferred Units section below.
	During the year ended December 31, 2014, Crestwood Midstream issued 387,991 Preferred Units to its preferred unitholders in lieu of paying a cash distribution. On February 13, 2015, Crestwood Midstream issued 414,325 Preferred Units to its preferred unitholders for the quarter ended December 31, 2014 in lieu of paying a cash distribution.
	Crestwood Niobrara Preferred Unitholders. Crestwood Midstream serves as the managing member of Crestwood Niobrara and, subject to certain restrictions, it has the ability to redeem GE’s preferred interest in either cash or Crestwood Midstream common units at an amount equal to the face amount of the preferred units plus an applicable return. During the years ended December 31, 2014 and 2013, Crestwood Niobrara issued 11,419,241 and 2,161,657 preferred units to GE in lieu of paying a cash distribution. On January 30, 2015, Crestwood Niobrara issued 3,680,570 preferred units to GE in lieu of paying a cash distribution. Beginning with the first quarter of 2015, Crestwood Niobrara no longer has the option to pay distributions to GE by issuing additional preferred units in lieu of paying a cash distribution.
	Other Partners' Capital Transactions
Equity Distribution Agreement
On July 10, 2014, Crestwood Midstream entered into an equity distribution agreement with Morgan Stanley & Co. LLC, Merrill Lynch, Pierce, Fenner & Smith Incorporated, Citigroup Global Markets Inc., J.P. Morgan Securities LLC, RBC Capital Markets, LLC, SunTrust Robinson Humphrey, Inc. and Wells Fargo Securities, LLC (each, a Manager), under which it may offer and sell from time to time through one or more of the Managers, its common units having an aggregate offering price of up to $300.0 million. Common units sold pursuant to this at-the-market (ATM) equity distribution program will be issued under a registration statement that became effective on May 27, 2014. Crestwood Midstream will pay the Managers an aggregate fee of up to 2.0% of the gross sales price per common unit sold under its ATM program. Crestwood Midstream has not issued any common units under this equity distribution program as of December 31, 2014 and through the date of this filing.
Crestwood Merger
In conjunction with Crestwood Holdings’ acquisition of our general partner, we issued 4,387,889 subordinated units, which are considered limited partnership interests, and have the same rights and obligations as our common units, except that the subordinated units are entitled to receive distributions of available cash for a particular quarter only after each of our common units has received a distribution of at least $0.13 for that quarter.  Our subordinated units convert to common units after (i) our common units have received a cumulative distribution in excess of $0.52 during a consecutive four quarter period; and (ii) our Adjusted Operating Surplus (as defined in the agreement) exceeds the distribution on a fully dilutive basis.
As discussed in Note 1, in conjunction with the Crestwood Merger, Legacy Crestwood unitholders received 1.07 units of Inergy Midstream units for each Legacy Crestwood unit they owned and as a result, there were no Legacy Crestwood common or Class D units outstanding immediately following the merger. In addition, Legacy Crestwood unitholders also received a $34.9 million distribution, $10 million of which was funded as a non-cash contribution from Crestwood Holdings and is reflected on our consolidated statements of partners’ capital as contribution from Crestwood Holding LLC for the year ended December 31, 2013. We reflected the distribution of $34.9 million as distributions to non-controlling partners on our consolidated statements of partners’ capital for the year ended December 31, 2013.
In conjunction with the Crestwood Merger, the restricted units outstanding under the Legacy Inergy long-term incentive plan were modified to accelerate the vesting of certain outstanding awards on December 31, 2013.  We reflected the cash paid of approximately $11.8 million related to these vested units as distributions to partners on our consolidated statements of cash flows for the year ended December 31, 2013.
Following the closing of the Crestwood Merger, Crestwood Holdings exchanged 7,100,000 common units of CMLP for 14,300,000 common units of CEQP pursuant to an option obtained on June 19, 2013 when it acquired our general partner.  This exchange resulted in a $182.3 million decrease to the interest of non-controlling partners and a $182.3 million increase to partners' capital on our consolidated statements of partners' capital.
Acquisitions and Other
CMM. In February 2012, Legacy Crestwood and Crestwood Holdings formed the CMM joint venture. Legacy Crestwood contributed approximately $131.3 million for a 35% membership interest and Crestwood Holdings contributed approximately $243.8 million for a 65% membership interest. On January 8, 2013, Legacy Crestwood acquired Crestwood Holdings’ 65% membership interest in CMM for approximately $258.0 million, which was funded through $129.0 million of borrowings under the Legacy Crestwood credit facility, the issuance of 6,190,469 Class D units and the issuance of 133,060 general partner units to the Legacy Crestwood general partner. As a result of the acquisition of the additional membership interest, Legacy Crestwood had the ability to control CMM’s operating and financial decisions and policies. The transaction was accounted for as a reorganization of entities under common control and accordingly, the historical results of Legacy Crestwood were retrospectively adjusted to reflect the change in reporting entity as of and for the year ended December 31, 2012. We reflected the $243.8 million contribution by Crestwood Holdings as contributions from non-controlling partners in our consolidated statements of cash flows and statements of partners’ capital for the year ended December 31, 2012. The issuances of the Class D and general partner units in conjunction with the acquisition of the additional interest in CMM were reflected as distributions for additional interest in Crestwood Marcellus Midstream LLC in our consolidated statements of cash flows and statements of partners’ capital for the year ended December 31, 2013.
Arrow. On November 7, 2013, Crestwood Midstream issued 8,826,125 common units as partial consideration of the Arrow Acquisition. See Note 3 for additional information regarding the Arrow Acquisition.
Other. In connection with Crestwood Holdings’ acquisition of Legacy Crestwood, Legacy Crestwood GP agreed to pay Quicksilver conditional consideration in the form of potential additional cash payments of up to $72 million depending on the achievement of certain defined average volume targets above an agreed threshold for 2012.
In February 2012, Crestwood Holdings paid Quicksilver approximately $41.1 million on behalf of Legacy Crestwood GP associated with the average volumes achieved for 2011. We reflected this payment as a non-cash contribution from non-controlling partners on our consolidated statements of partners’ capital for the year ended December 31, 2012.   As of December 31, 2012, Quicksilver did not achieve their 2012 average volume target. As such, we determined that the estimated fair value of our remaining conditional consideration to Quicksilver was zero, and we recognized a gain of approximately $6.8 million for the year ended December 31, 2012 related to the elimination of the contingent liability.
In August 2012, Legacy Inergy contributed its retail propane operations to SPH.  In connection with this contribution, Legacy Inergy retained approximately 142,000 SPH units which we record at fair value each quarter.  The change in fair value is reflected in the consolidated statements of partners’ capital and the consolidated statements of comprehensive income.

Equity_Plans

Equity Plans	12 Months Ended
	Dec. 31, 2014
Equity [Abstract]
Equity Plan	Equity Plans
	Long-term incentive awards are granted under the Crestwood Equity Partners LP Long Term Incentive Plan (Crestwood LTIP) and the Crestwood Midstream Partners LP Long Term Incentive Plan (Crestwood Midstream LTIP) in order to align the economic interests of key employees and directors with those of CEQP and Crestwood Midstream's common unitholders and to provide an incentive for continuous employment. Long-term incentive compensation consist solely of grants of restricted common units (which represent limited partner interests of CEQP and Crestwood Midstream) which vest based upon continued service.
	During 2014, we have issued restricted unit awards, which were approved by either CEQP's and Crestwood Midstream's Board compensation committee or pursuant to the authority granted by the Chief Executive Officer, to certain key employees. These awards vest upon continued service with the Company.
	Crestwood Equity
	Crestwood LTIP. The following table summarizes information regarding restricted unit activity during the year ended December 31, 2014:
			Units			Weighted-Average Grant Date Fair Value
	Unvested - January 1, 2014		493,543			$	13.96
	Vested - restricted units		(449,936	)		$	13.97
	Granted - restricted units		1,377,461			$	13.23
	Forfeited		(105,188	)		$	13.73
	Unvested - December 31, 2014		1,315,880			$	13.21
	As of December 31, 2014 and 2013, we had total unamortized compensation expense of approximately $8.1 million and $1.6 million related to restricted units, which we expect will be amortized during the next three years (or sooner in certain cases, which generally represents the original vesting period of these instruments), except for grants to non-employee directors of our general partner, which vest over one year.  We recognized compensation expense of approximately $10.1 million (including $6.9 million that was allocated to Crestwood Midstream) under the Crestwood LTIP during the year ended December 31, 2014, and $10.9 million (including $4.4 million that was allocated to Crestwood Midstream) under the Legacy Inergy long-term incentive plan during the year ended December 31, 2013, which is included in general and administrative expenses on our consolidated statements of operations.  We granted restricted units with a grant date fair value of approximately $18.2 million during the year ended December 31, 2014. In January 2015, we filed a registration statement on Form S-8 with the SEC to register an additional 10,000,000 units under the plan for a total of 15,000,000 units registered with the SEC. As of February 13, 2015, we had 12,613,231 units available for issuance under the Crestwood LTIP.
	Under the Crestwood LTIP, participants who have been granted restricted units may elect to have us withhold common units to satisfy minimum statutory tax withholding obligations arising in connection with the vesting of non-vested common units. Any such common units withheld are returned to the Crestwood LTIP on the applicable vesting dates, which correspond to the times at which income is recognized by the employee. When we withhold these common units, we are required to remit to the appropriate taxing authorities the fair value of the units withheld as of the vesting date. The number of units withheld is determined based on the closing price per common unit as reported on the NYSE on such dates. During the years ended December 31, 2014 and 2013, we withheld 159,435 and 362,565 common units to satisfy employee tax withholding obligations.
	Unit Purchase Plan. Prior to September 2014, Crestwood Equity's general partner sponsored a unit purchase plan for its employees and the employees of its affiliates. The unit purchase plan permitted participants to purchase common units in market transactions from Crestwood Equity, the general partners or any other person. All purchases were made in market transactions, although the plan allowed Crestwood Equity to issue additional units. Under the plan, the general partner had the option to match each participant's cash base pay or salary deferrals by an amount up to 10% of such deferrals and have such amount applied toward the purchase of additional units. The general partner also agreed to pay the brokerage commissions, transfer taxes and other transaction fees associated with a participant's purchase of common units. This plan was discontinued in September 2014. There were 15,369 units purchased through the unit purchase plan by Crestwood Equity and its employees during the year ended December 31, 2014.
	Crestwood Midstream
	Crestwood Midstream LTIP. The following table summarizes information regarding restricted unit activity during the year ended December 31, 2014:
			Units			Weighted-Average Grant Date Fair Value
	Unvested - January 1, 2014		250,557			$	22.13
	Vested - restricted units		(208,361	)		$	22.15
	Granted - restricted units		871,078			$	23.25
	Forfeited		(78,478	)		$	23.33
	Unvested - December 31, 2014		834,796			$	23.18
	As of December 31, 2014 and 2013, we had total unamortized compensation expense of approximately $9.5 million and $1.8 million related to restricted units issued under the Crestwood Midstream LTIP, which we expect will be amortized during the next three years (or sooner in certain cases, which generally represents the original vesting period of these instruments), except for grants to non-employee directors of the general partner of CEQP, which vest over one year. Crestwood Midstream recognized compensation expense of approximately $11.2 million and $11.4 million (including $6.5 million recognized by Legacy Crestwood in 2013 as discussed below) during the years ended December 31, 2014 and 2013, which is included in general and administrative expenses on our consolidated statements of operations. We granted restricted units with a grant date fair value of approximately $20.3 million during the year ended December 31, 2014. As of December 31, 2014, we had 17,629,657 units available for issuance under the Crestwood Midstream LTIP.
	Under the Crestwood Midstream LTIP, participants who have been granted restricted units may elect to have common units withheld to satisfy minimum statutory tax withholding obligations arising in connection with the vesting of non-vested common units. Any such common units withheld are returned to the Crestwood Midstream LTIP on the applicable vesting dates, which correspond to the times at which income is recognized by the employee. When such common units are withheld, Crestwood Midstream is required to remit to the appropriate taxing authorities the fair value of the units withheld as of the vesting date. The number of units withheld is determined based on the closing price per common unit as reported on the NYSE on such dates. During the year ended December 31, 2014, Crestwood Midstream withheld 71,484 common units to satisfy employee tax withholding obligations.
	Employee Unit Purchase Plan. Beginning in September 2014, the board of directors of Crestwood Midstream's general partner made available an employee unit purchase plan under which employees of the general partner may purchase Crestwood Midstream's common units through payroll deductions up to a maximum of 10% of the employees' eligible compensation. Under the plan, CMLP may purchase its common units on the open market for the benefit of participating employees based on their payroll deductions. In addition, CMLP may contribute an additional 10% of participating employees' payroll deductions to purchase additional CMLP common units for participating employees. Unless increased by the board of directors of Crestwood Midstream's general partner, the maximum number of common units that may be purchased under the plan is 200,000. In January 2015, there were 2,011 common units purchased through the unit purchase plan for the year ended December 31, 2014.
	Legacy Crestwood
	Long-Term Incentive Plan. Prior to the Crestwood Merger, awards of phantom and restricted units were granted under the Legacy Crestwood Fourth Amended and Restated 2007 Equity Plan (the 2007 Equity Plan). The 2007 Equity Plan was terminated in conjunction with the Crestwood Merger. All of the unvested phantom and restricted units became vested upon consummation of the Crestwood Merger and all unamortized compensation expense related to those units was recognized on that date. The following table summarizes information regarding phantom and restricted unit activity:
		Payable In Cash						Payable In Units
		Units			Weighted-			Units		Weighted-
					Average Grant					Average Grant
					Date Fair					Date Fair
					Value					Value
	Unvested - December 31, 2012	8,312			$	26.45		221,992		$	28.35
	Vested - phantom units	(7,958	)		$	26.48		(329,825	)	$	26.69
	Vested - restricted units	—			$	—		(74,760	)	$	25.6
	Granted - phantom units	—			$	—		161,807		$	24.33
	Granted - restricted units	—			$	—		27,900		$	24.86
	Canceled - phantom units	(354	)		$	25.81		(7,114	)	$	27.96
	Unvested - December 31, 2013	—			$	—		—		$	—
	As discussed above, the vesting period of our phantom and restricted units were accelerated upon consummation of the Crestwood Merger.  Crestwood Midstream recognized compensation expense under the 2007 Equity Plan of approximately $6.5 million and $1.9 million for the years ended December 31, 2013 and 2012, included in operating expenses on our consolidated statements of income. Crestwood Midstream granted phantom and restricted units under the 2007 Equity Plan with a grant date fair value of approximately $4.6 million and $4.7 million for the years ended December 31, 2013 and 2012. During the year ended December 31, 2013, Crestwood Midstream withheld 21,014 common units to satisfy employee tax withholding obligations.

Employee_Benefit_Plan

Employee Benefit Plan	12 Months Ended
	Dec. 31, 2014
Postemployment Benefits [Abstract]
Employee Benefit Plans	Employee Benefit Plan
	A 401(k) plan is available to all of our employees after meeting certain requirements. The plan permits employees to make contributions up to 75% of their salary, up to statutory limits, which was $17,500 in 2014 and 2013. We match 100% of participants basic contribution up to 6% of eligible compensation. Employees may participate in the plans immediately and certain employees are not eligible for matching contributions until after a 90-day waiting period. Aggregate matching contributions made by us were $3.8 million and $0.5 million in 2014 and 2013. Neither Legacy Crestwood GP nor Legacy Crestwood had any employees. Employees of Crestwood Holdings provided services to Legacy Crestwood GP and Legacy Crestwood pursuant to an omnibus agreement.

Commitments_and_Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies
	Legal Proceedings
	Property Taxes. In conjunction with the sale of our interest in Tres Palacios to Tres Holdings, we retained the liability of Tres Palacios for certain tax matters, including the property taxes litigation in which we challenged the Matagorda County Appraisal District that the assessed value was over the market value for the tax years from 2012 to 2013. For those years, the total difference in taxes between the assessed value and the market value is approximately $12 million. These lawsuits remain pending and the outcome is not yet determined. In January 2015, we settled the lawsuit related to the 2011 tax year with the Matagorda County Appraisal District.
	Arrow Acquisition Class Action Lawsuit. Prior to the completion of the Arrow Acquisition on November 8, 2013, a train transporting over 50,000 barrels of crude oil produced in North Dakota derailed in Lac Megantic, Quebec, Canada on July 6, 2013. The derailment resulted in the death of 47 people, injured numerous others, and caused severe damage to property and the environment.  In October 2013, certain individuals suffering harm in the derailment filed a motion to certify a class action lawsuit in the Superior Court for the District of Megantic, Province of Quebec, Canada, on behalf of all persons suffering loss in the derailment (the Class Action Suit).
	In March 2014, the plaintiffs filed their fourth amended motion to name Arrow and numerous other energy companies as additional defendants in the class action lawsuit. The plaintiffs have named at least 53 defendants purportedly involved in the events leading up to the derailment, including the producers and sellers of the crude being transported, the midstream companies that transported the crude from the well head to the rail system, the manufacturers of the rail cars used to transport the crude, the railroad companies involved, the insurers of these companies, and the Canadian Attorney General.  The plaintiffs allege, among other things, that Arrow (i) was a producer of the crude oil being transported on the derailed train, (ii) was negligent in failing to properly classify the crude delivered to the trucks that hauled the crude to the rail loading terminal, and (iii) owed a duty to the petitioners to ensure the safe transportation of the crude being transported.  The motion to authorize the class action and motions in opposition were heard by the Court in June 2014. We anticipate a ruling from the Judge on the Petitioners' motion to authorize the class action in the first quarter of 2015.
	There are three other lawsuits related to the Class Action Suit. Montreal Main & Atlantic Railway filed bankruptcy actions in both the U.S. Bankruptcy Court for the District of Maine and in the Canadian Bankruptcy Court. In addition, a lawsuit was filed in Cook County, Illinois on behalf of the deceased claimants, which is currently stayed due to the bankruptcy proceeding. We are not currently named as a defendant in these additional lawsuits; however, we have been notified by the bankruptcy trustees of a proposal to contribute to a settlement in exchange for a release from all claims related to the Class Action Suit. We are currently evaluating this proposal and negotiating with the Bankruptcy Trustee.
	We will vigorously defend ourselves and, to the extent these actions proceed, we believe we have meritorious defenses to the claims.  Because these related actions are in the early stages of the proceeding, we are unable to estimate a reasonably possible loss or range of loss in this matter.  We also believe these claims are insurable under our insurance policy and we have notified our insurance company of them.
	When we were served with the Class Action Suit, we notified the former owners of the Arrow system that the claims alleged in the Class Action Suit would, if true, result in breaches of certain representations and warranties made by the former sellers in the agreement under which we acquired Arrow. As part of the acquisition, we deposited 3,309,797 of our common units into an escrow account to cover potential indemnification claims made by us on or before December 31, 2014. Subject to indemnification claims paid out with escrowed units and any outstanding claims outstanding at year end, all common units remaining in the escrow account on January 1, 2015 were to be released to the former owners. In December 2014, we notified the escrow agent of our indemnification notices delivered to the former owners and instructed the escrow agent not to release any escrowed units to the former owners. On February 19, 2015, we received a summons for an action filed against us in the Supreme Court of the State of New York (County of New York), under which the former owners have asserted our indemnification notices regarding the Class Action Suit and our notice to the escrow agent breach the terms of the merger and escrow agreements and the implied covenant of good faith and fair dealing.  The former owners have requested declaratory and injunctive relief, as well as monetary damages. Although our insurance policies would not cover this action, we believe we have meritorious defenses to this lawsuit and will aggressively defend ourselves. We are unable to estimate a reasonably possible loss or range of loss in this matter due to the recent filing of this lawsuit.
	General. We are periodically involved in litigation proceedings. If we determine that a negative outcome is probable and the amount of loss is reasonably estimable, then we accrue the estimated amount. The results of litigation proceedings cannot be predicted with certainty. We could incur judgments, enter into settlements or revise our expectations regarding the outcome of certain matters, and such developments could have a material adverse effect on our results of operations or cash flows in the period in which the amounts are paid and/or accrued. As of December 31, 2014 and 2013, we had $1.0 million and less than $0.1 million accrued for our outstanding legal matters. Based on currently available information, we believe it is remote that future costs related to known contingent liability exposures for which we can estimate will exceed current accruals by an amount that would have a material adverse impact on our consolidated financial statements. As we learn new facts concerning contingencies, we reassess our position both with respect to accrued liabilities and other potential exposures.
	Any loss estimates are inherently subjective, based on currently available information, and are subject to management's judgment and various assumptions. Due to the inherently subjective nature of these estimates and the uncertainty and unpredictability surrounding the outcome of legal proceedings, actual results may differ materially from any amounts that have been accrued.
	Regulatory Compliance
	In the ordinary course of our business, we are subject to various laws and regulations. In the opinion of our management, compliance with current laws and regulations will not have a material effect on its results of operations, cash flows or financial condition.
	Environmental Compliance
	During the year ended December 31, 2014, we experienced three releases totaling approximately 28,000 barrels of produced water on our Arrow water gathering system located on the Fort Berthold Indian Reservation in North Dakota. We immediately notified the National Response Center, the Three Affiliated Tribes and numerous other regulatory authorities, and thereafter contained and cleaned up the releases completely and placed the impacted segments of these water lines back into service. During the year ended December 31, 2014, we recognized $4.6 million of operations and maintenance expense related to these releases, of which $1.1 million was included in other current liabilities on our balance sheet as of December 31, 2014. We will continue our remediation efforts to ensure the impacted lands are restored to their prior state, and we may potentially be subject to fines and penalties. We believe these releases are insurable events under our policies, and we have notified our insurance companies of these events. As of December 31, 2014, we had no amounts accrued for fines and penalties. We have not recorded an insurance receivable as of December 31, 2014.
	Our operations are subject to stringent and complex laws and regulations pertaining to health, safety, and the environment. We are subject to laws and regulations at the federal, state and local levels that relate to air and water quality, hazardous and solid waste management and disposal and other environmental matters. The cost of planning, designing, constructing and operating our facilities must incorporate compliance with environmental laws and regulations and safety standards. Failure to comply with these laws and regulations may trigger a variety of administrative, civil and potentially criminal enforcement measures. At December 31, 2014, our accrual of approximately $1.1 million was primarily related to the Arrow water releases described above, which is based on our undiscounted estimate of amounts we will spend on compliance with environmental and other regulations. We estimate that our potential liability for reasonably possible outcomes related to our environmental exposures (including the Arrow water releases described above) could range from approximately $1.1 million to $1.5 million. Our accrual and potential exposure related to our environmental matters was immaterial at December 31, 2013.
	Self-Insurance
	We utilize third-party insurance subject to varying retention levels of self-insurance, which management considers prudent. Such self-insurance relates to losses and liabilities primarily associated with medical claims, workers' compensation claims and general, product, vehicle and environmental liability. Losses are accrued based upon management's estimates of the aggregate liability for claims incurred using certain assumptions followed in the insurance industry and based on past experience. The primary assumption utilized is actuarially determined loss development factors. The loss development factors are based primarily on historical data. Our self insurance reserves could be affected if future claim developments differ from the historical trends. We believe changes in health care costs, trends in health care claims of our employee base, accident frequency and severity and other factors could materially affect the estimate for these liabilities. We continually monitor changes in employee demographics, incident and claim type and evaluates our insurance accruals and adjusts our accruals based on our evaluation of these qualitative data points. We are liable for the development of claims for our disposed retail propane operations, provided they were reported prior to August 1, 2012. At December 31, 2014 and 2013, our self-insurance reserves were $14.6 million and $15.8 million. We estimate that $9.7 million of this balance will be paid subsequent to December 31, 2015. As such, $9.7 million has been classified in other long-term liabilities on our consolidated balance sheets.
	Commitments and Purchase Obligations
	Operating Leases. We also maintain operating leases in the ordinary course of our business activities. These leases include those for office buildings, crude oil railroad cars and other operating facilities and equipment. The terms of the agreements vary from 2015 until 2032.
	Future minimum lease payments under noncancelable operating leases for the next five years ending December 31 and in total thereafter consist of the following (in millions):
	Year Ending
	December 31,
	2015	$	16.9
	2016	15.5
	2017	12.9
	2018	11
	2019	9.9
	Thereafter	17.5
	Total minimum lease payments	$	83.7
	Rent expense for operating leases for the years ended December 31, 2014, 2013 and 2012, totaled $41.8 million, $16.4 million and $7.4 million.
	Capital Leases. We have a treating facility and certain auto leases which are accounted for as capital leases. The terms of the agreements vary from 2015 until 2018. We recorded amortization of expense of $3.3 million, $3.6 million and $3.1 million for the years ended December 31, 2014, 2013 and 2012.
	Future minimum lease payments related to our capital leases at December 31, 2014 are as follows (in millions):
	Year Ending
	December 31,
	2015	$	2.2
	2016	1.6
	2017	1.2
	2018	0.4
	Total payments	5.4
	Imputed interest	(0.1		)
	Present value of future payments	$	5.3
	Our capital lease liabilities were $5.3 million and $4.7 million at December 31, 2014 and 2013, and are included in accrued expenses and other liabilities and other long-term liabilities on our consolidated balance sheets.
	Purchase Commitments. We periodically enter into agreements with suppliers to purchase fixed quantities of NGLs, distillates, crude oil and natural gas at fixed prices. At December 31, 2014, the total of these firm purchase commitments was $242.9 million, substantially all of which will occur over the course of the next twelve months. We also enter into non-binding agreements with suppliers to purchase quantities of NGLs, distillates and natural gas at variable prices at future dates at the then prevailing market prices.
	We have entered into certain purchase commitments in connection with the identified growth projects primarily related to the Arrow development project in the Bakken Shale, certain upgrades to the US Salt facility and growth and maintenance obligations related to our G&P segment. At December 31, 2014, the total of our storage and transportation and NGL and crude services operations' firm purchase commitments was approximately $22.7 million and our gathering and processing segment's purchase commitments totaled approximately $9.8 million. The majority of the purchases associated with these commitments are expected to occur over the next twelve months.

Related_Party_Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2014
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions
	Our general partner is indirectly owned by Crestwood Holdings. The affiliates of Crestwood Holdings and its owners are considered our related parties, including Sabine Oil and Gas LLC and Mountaineer Keystone LLC.
	We enter into transactions with our affiliates within the ordinary course of business and the services are based on the same terms as non-affiliates, including gas gathering and processing services under long-term contracts, product purchases and various operating agreements. Prior to the Crestwood Merger, we were managed and operated by the directors and officers of Legacy Crestwood’s general partner. We had an omnibus agreement with Crestwood Holdings and the Legacy Crestwood general partner under which Legacy Crestwood reimbursed Crestwood Holdings for the provision of various general and administrative services for its benefit and for direct expenses incurred by Crestwood Holdings on its behalf. Crestwood Holdings billed Legacy Crestwood directly for certain general and administrative costs and allocated a portion of its general and administrative costs to Legacy Crestwood.
	The following table shows revenues, costs of goods sold and general and administrative expenses from our affiliates for the years December 31, 2014, 2013 and 2012 (in millions):
		Year Ended December 31,
		2014 (1)		2013		2012
	Gathering and processing revenues	$	3	$	74.9	$	113.7
	Gathering and processing costs of product/services sold(2)	$	42.2	$	32.5	$	15.2
	General and administrative expenses	$	0.5	$	25.3	$	19.5
	(1) Concurrent with the Crestwood Merger, Quicksilver Resources Inc. (Quicksilver) is no longer a related party, and as a result our transactions with
	Quicksilver subsequent to June 19, 2013, are now considered non-affiliated transactions.
	(2) Represents natural gas purchases from Sabine Oil and Gas.
	The following table shows accounts receivable and accounts payable from our affiliates as of December 31, 2014 and 2013 (in millions):
		December 31, 2014		December 31, 2013
	Accounts receivable	$	0.6	$	—
	Accounts payable	$	5.6	$	3.6
	Following the closing of the Crestwood Merger on October 7, 2013, Crestwood Holdings exchanged 7,100,000 common units of Crestwood Midstream for 14,300,000 of our common units pursuant to an option granted to Crestwood Holdings when it acquired our general partner.

Segments

Segments	12 Months Ended
	Dec. 31, 2014
Segment Reporting [Abstract]
Segments	Segments
	Financial Information
	We have three operating and reportable segments: (i) gathering and processing operations; (ii) storage and transportation operations; and (iii) NGL and crude services operations. Our gathering and processing operations engage in the gathering, processing, treating, compression, transportation and sales of natural gas and the delivery of NGLs. Our storage and transportation operations provide regulated natural gas storage and transportation services to producers, utilities and other customers. Our NGL and crude services operations provide NGL processing and fractionation, NGLs and crude oil gathering, storage, marketing and transportation, supply and logistics services to producers, refiners, marketers, and other customers that effectively provide flow assurances to our customers, as well as the production and sale of salt products. Our corporate operations include all general and administrative expenses that are not allocated to our reportable segments. We assess the performance of our operating segments based on EBITDA, which represents operating income plus depreciation, amortization and accretion expense.
	Below is a reconciliation of our net income to EBITDA (in millions):
		Year Ended December 31,
		2014			2013			2012
	Net income (loss)	$	(10.4	)	$	(50.6	)	$	24.4
	Add:
	Interest and debt expense, net	127.1			77.9			35.8
	Provision for income taxes	1.1			1			1.2
	Depreciation, amortization and accretion	285.3			167.9			73.2
	EBITDA	$	403.1		$	196.2		$	134.6
	The following tables summarize the reportable segment data for the years ended December 31, 2014, 2013 and 2012 (in millions).
		Year Ended December 31, 2014
		Gathering and Processing			Storage and Transportation			NGL and Crude Services			Intersegment			Corporate			Total
	Revenues	$	332.5		$	192.9		$	3,406.90		$	(1.0	)	$	—		$	3,931.30
	Costs of product/services sold	71.3			24.8			3,070.20			(1.0		)	—			3,165.30
	Operations and maintenance expense	62.9			23.3			117.1			—			—			203.3
	General and administrative expense	—			—			—			—			100.2			100.2
	Gain (loss) on long-lived assets, net	(32.7		)	33.8			(3.0		)	—			—			(1.9		)
	Goodwill impairment	(18.5		)	—			(30.3		)	—			—			(48.8		)
	Loss on contingent consideration	(8.6		)	—			—			—			—			(8.6		)
	Earnings (loss) from unconsolidated affiliates	0.5			0.2			(1.4		)	—			—			(0.7		)
	Other income, net	—			—			—			—			0.6			0.6
	EBITDA	$	139		$	178.8		$	184.9		$	—		$	(99.6	)	$	403.1
	Goodwill	$	338.3		$	726.3		$	1,427.20		$	—		$	—		$	2,491.80
	Total assets	$	2,645.00		$	1,981.20		$	3,631.30		$	—		$	203.9		$	8,461.40
	Purchases of property, plant and equipment	$	245.7		$	9.7		$	160.4		$	—		$	8.2		$	424
		Year Ended December 31, 2013
		Gathering and Processing			Storage and Transportation			NGL and Crude Services			Intersegment			Corporate			Total
	Revenues	$	291.2		$	104.2		$	1,031.30		$	—		$	—		$	1,426.70
	Costs of product/services sold	56.6			15.7			930			—			—			1,002.30
	Operations and maintenance expense	54.9			12.1			37.6			—			—			104.6
	General and administrative expense	—			—			—			—			93.5			93.5
	Gain (loss) on long-lived assets	5.4			—			(0.1		)	—			—			5.3
	Goodwill impairment	(4.1		)	—			—			—			—			(4.1		)
	Loss on contingent consideration	(31.4		)	—			—			—			—			(31.4		)
	Earnings (loss) from unconsolidated affiliates	0.1			—			(0.2		)	—			—			(0.1		)
	Other income, net	—			—			—			—			0.2			0.2
	EBITDA	$	149.7		$	76.4		$	63.4		$	—		$	(93.3	)	$	196.2
	Goodwill	$	356.8		$	936.5		$	1,258.90		$	—		$	—		$	2,552.20
	Total assets	$	2,507.30		$	2,369.10		$	3,465.80		$	—		$	181		$	8,523.20
	Purchases of property, plant and equipment	$	271.2		$	18		$	56.8		$	—		$	1		$	347
		Year Ended December 31, 2012
		Gathering and Processing			Storage and Transportation			NGL and Crude Services			Intersegment			Corporate			Total
	Revenues	$	239.5		$	—		$	—		$	—		$	—		$	239.5
	Costs of product/services sold	39			—			—			—			—			39
	Operations and maintenance expense	43.1			—			—			—			—			43.1
	General and administrative expense	—			—			—			—			29.6			29.6
	Gain on contingent consideration	6.8			—			—			—			—			6.8
	EBITDA	$	164.2		$	—		$	—		$	—		$	(29.6	)	$	134.6
	Goodwill	$	352.2		$	—		$	—		$	—		$	—		$	352.2
	Total assets	$	2,278.90		$	—		$	—		$	—		$	22.7		$	2,301.60
	Purchases of property, plant and equipment	$	51.5		$	—		$	—		$	—		$	1.1		$	52.6
	Major Customers
	For the year ended December 31, 2014, Tesoro had revenues of $465.2 million which exceeded 10% of our total consolidated revenues. Revenues from Tesoro are reflected in our NGL and crude services segment. No customer accounted for 10% or more of our total consolidated revenues for the year ended December 31, 2013. For the year ended December 31, 2012, Quicksilver and Antero had revenues of approximately $112.6 million and $25.5 million, which exceeded 10% of our total consolidated revenues. Revenues from Quicksilver and Antero are reflected in our gathering and processing segment.

Condensed_Consolidating_Financ

Condensed Consolidating Financial Information	12 Months Ended
	Dec. 31, 2014
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
Condensed Consolidating Financial Information Disclosure	Condensed Consolidating Financial Information
	We are a holding company and own no operating assets and have no significant operations independent of our subsidiaries. Obligations under the CEQP Senior Notes and the CEQP Credit Facility are jointly and severally guaranteed by our wholly owned domestic subsidiaries. Legacy Crestwood GP and Crestwood Midstream and its wholly owned subsidiaries (collectively, Non-Guarantor Subsidiaries) do not guarantee our obligations under CEQP Senior Notes or CEQP Credit Facility. CEQP Finance Corp., the co-issuer of the CEQP Senior Notes, is our 100% owned subsidiary and has no material assets, operations, revenues or cash flows other than those related to its service as co-issuer of our senior notes.
	As summarized in the table below, the condensed consolidating statement of cash flows for the year ended December 31, 2013 has been corrected for certain errors in presentation. There was no impact to our consolidated statement of cash flows for the year ended December 31, 2013.
		Parent						Guarantor Subsidiaries						Eliminations
		As Adjusted			As Previously Reported			As Adjusted			As Previously Reported			As Adjusted			As Previously Reported
		(in millions)
	Cash flows from operating activities:	$	(12.3	)	$	—		$	14.1		$	1.8		$	—		$	—
	Cash flows from investing activities:
	Capital contributions from consolidated affiliates, net and other	20.7			76			0.1			17			(20.7		)	(92.9		)
	Net cash provided by (used in) investing activities	20.7			76			(6.4		)	10.5			(20.7		)	(92.9		)
	Cash flows from financing activities:
	Proceeds from the issuance of long-term debt	394.1			—			—			394.1			—			—
	Principal payments on long-term debt	(333.3		)	—			—			(333.3		)	—			—
	Distributions paid to partners	(68.4		)	(76.0		)	—			(59.1		)	26.2			92.9
	Change in intercompany balances	0.4			—			(0.4		)	—			—			—
	Other	(1.1		)	0.1			(4.9		)	(11.6		)	(5.5		)	—
	Net cash provided by (used in) financing activities	(8.3		)	(75.9		)	(5.3		)	(9.9		)	20.7			92.9
	The tables below present condensed consolidating financial statements for us (parent) on a stand-alone, unconsolidated basis, and our combined guarantor and combined non-guarantor subsidiaries as of and for the years ended December 31, 2014 and 2013. The financial information may not necessarily be indicative of the results of operations, cash flows or financial position had the subsidiaries operated as independent entities. As discussed in Note 2, the accounting for the reverse acquisition of Legacy Inergy results in Legacy Inergy's historical operations being acquired on June 19, 2013. The CEQP Senior Notes are thus not included in the financial statements prior to June 19, 2013. Since Legacy Crestwood GP (the accounting predecessor) does not guarantee any debt, the condensed consolidated financial statements do not include financial information for the year ended December 31, 2012.
	Condensed Consolidating Balance Sheet
	31-Dec-14
	(in millions)
		Parent			Guarantor			Non-			Eliminations			Consolidated
					Subsidiaries			Guarantor
								Subsidiaries
	Assets
	Current assets:
	Cash	$	3.7		$	0.5		$	4.6		$	—		$	8.8
	Accounts receivable	—			137.5			241.5			—			379
	Accounts receivable - related party	—			0.3			0.3			—			0.6
	Accounts receivable - intercompany	3.2			—			—			(3.2		)	—
	Total accounts receivable	3.2			137.8			241.8			(3.2		)	379.6
	Inventories	—			38.6			8			—			46.6
	Other current assets	—			84.4			18.7			—			103.1
	Total current assets	6.9			261.3			273.1			(3.2		)	538.1
	Property, plant and equipment, net	2.5			227.1			3,664.20			—			3,893.80
	Goodwill and intangible assets, net	1.7			706.7			3,014.70			—			3,723.10
	Investment in consolidated affiliates	5,971.20			—			—			(5,971.2		)	—
	Investment in unconsolidated affiliates	—			—			295.1			—			295.1
	Other assets	—			9.9			1.4			—			11.3
	Total assets	$	5,982.30		$	1,205.00		$	7,248.50		$	(5,974.4	)	$	8,461.40
	Liabilities and partners' capital
	Current liabilities:
	Accounts payable	$	—		$	109.5		$	126.1		$	—		$	235.6
	Accounts payable - related party	—			2.5			3.1			—			5.6
	Accounts payable - intercompany	—			—			3.2			(3.2		)	—
	Total accounts payable	—			112			132.4			(3.2		)	241.2
	Other current liabilities	4.9			56.1			122.7			—			183.7
	Total current liabilities	4.9			168.1			255.1			(3.2		)	424.9
	Long-term liabilities:
	Long-term debt, less current portion	380			—			2,012.80			—			2,392.80
	Other long-term liabilities	12.9			15.1			31.2			—			59.2
	Total long-term liabilities	392.9			15.1			2,044.00			—			2,452.00
	Partners' capital	776.2			1,021.80			141.1			(1,162.9		)	776.2
	Interest of non-controlling partners in subsidiaries	4,808.30			—			4,808.30			(4,808.3		)	4,808.30
	Total partners' capital	5,584.50			1,021.80			4,949.40			(5,971.2		)	5,584.50
	Total liabilities and partners' capital	$	5,982.30		$	1,205.00		$	7,248.50		$	(5,974.4	)	$	8,461.40
	Condensed Consolidating Balance Sheet
	31-Dec-13
	(in millions)
		Parent			Guarantor			Non-			Eliminations			Consolidated
					Subsidiaries			Guarantor
								Subsidiaries
	Assets
	Current assets:
Cash	$	0.1		$	2.4		$	2.7		$	—		$	5.2
Accounts receivable	—			207.5			205.1			—			412.6
Accounts receivable - intercompany	—			—			—			—			—
Total accounts receivable	—			207.5			205.1			—			412.6
Inventories	—			66.6			7			—			73.6
Other current assets	—			25.8			10.2			(5.4		)	30.6
Total current assets	0.1			302.3			225			(5.4		)	522
Property, plant and equipment, net	—			400.9			3,504.40			—			3,905.30
Goodwill and intangible assets, net	—			742.4			3,170.20			—			3,912.60
Investment in consolidated affiliates	5,927.10			—			—			(5,927.1		)	—
Investment in unconsolidated affiliates	—			—			151.4			—			151.4
Other assets	—			10.2			21.7			—			31.9
Total assets	$	5,927.20		$	1,455.80		$	7,072.70		$	(5,932.5	)	$	8,523.20
Liabilities and partners' capital
Current liabilities:
Accounts payable	$	—		$	218.3		$	157.1		$	—		$	375.4
Accounts payable - related party	—			—			3.6			—			3.6
Accounts payable - intercompany	—			—			—			—			—
Total accounts payable	—			218.3			160.7			—			379
Other current liabilities	4.2			61.6			156.7			(5.4		)	217.1
Total current liabilities	4.2			279.9			317.4			(5.4		)	596.1
Long-term liabilities:
Long-term debt, less current portion	393			—			1,867.90			—			2,260.90
Other long-term liabilities	21.4			109.9			26.3			—			157.6
Total long-term liabilities	414.4			109.9			1,894.20			—			2,418.50
Partners' capital	831.6			1,066.00			184.1			(1,250.1		)	831.6
Interest of non-controlling partners in subsidiaries	4,677.00			—			4,677.00			(4,677.0		)	4,677.00
Total partners' capital	5,508.60			1,066.00			4,861.10			(5,927.1		)	5,508.60
Total liabilities and partners' capital	$	5,927.20		$	1,455.80		$	7,072.70		$	(5,932.5	)	$	8,523.20
Condensed Consolidating Statements of Operations
Year Ended December 31, 2014
(in millions)
	Parent			Guarantor			Non-			Eliminations			Consolidated
				Subsidiaries			Guarantor
							Subsidiaries
Revenues:
Gathering and processing	$	—		$	—		$	328.5		$	—		$	328.5
Storage and transportation	—			13.8			179.1			—			192.9
NGL and crude services	—			1,366.60			2,040.30			—			3,406.90
Related party	—			—			17.6			(14.6		)	3
	—			1,380.40			2,565.50			(14.6		)	3,931.30
Costs of product/services sold:
Gathering and processing	—			—			29.1			—			29.1
Storage and transportation	—			10.5			14.3			—			24.8
NGL and crude services	—			1,218.30			1,851.90			(1.0		)	3,069.20
Related party	—			13.6			42.2			(13.6		)	42.2
	—			1,242.40			1,937.50			(14.6		)	3,165.30
Expenses:
Operations and maintenance	—			64.3			139			—			203.3
General and administrative	8.5			6.3			85.4			—			100.2
Depreciation, amortization and accretion	—			44.7			240.6			—			285.3
	8.5			115.3			465			—			588.8
Other operating income (expense):
Gain (loss) on long-lived assets, net	—			31.7			(33.6		)	—			(1.9		)
Goodwill impairment	—			—			(48.8		)	—			(48.8		)
Loss on contingent consideration	—			—			(8.6		)	—			(8.6		)
Operating income (loss)	(8.5		)	54.4			72			—			117.9
Earnings (loss) from unconsolidated affiliates, net	—			—			(0.7		)	—			(0.7		)
Interest and debt expense, net	(15.7		)	—			(111.4		)	—			(127.1		)
Other income, net	—			0.6			—			—			0.6
Equity in net income (loss) of subsidiary	14.2			—			—			(14.2		)	—
Income (loss) before income taxes	(10.0		)	55			(40.1		)	(14.2		)	(9.3		)
Provision for income taxes	0.4			—			0.7			—			1.1
Net income (loss)	(10.4		)	55			(40.8		)	(14.2		)	(10.4		)
Net (income) loss attributable to non-controlling partners in subsidiaries	—			—			66.8			—			66.8
Net income (loss) attributable to partners	$	(10.4	)	$	55		$	26		$	(14.2	)	$	56.4
Condensed Consolidating Statements of Operations
Year Ended December 31, 2013
(in millions)
	Parent			Guarantor			Non-			Eliminations			Consolidated
				Subsidiaries			Guarantor
							Subsidiaries
Revenues:
Gathering and processing	$	—		$	—		$	216.3		$	—		$	216.3
Storage and transportation	—			14.1			90.1			—			104.2
NGL and crude services	—			761.2			270.1			—			1,031.30
Related party	—			—			82.1			(7.2		)	74.9
	—			775.3			658.6			(7.2		)	1,426.70
Costs of product/services sold:
Gathering and processing	—			—			24.1			—			24.1
Storage and transportation	—			7			8.7			—			15.7
NGL and crude services	—			699.6			230.4			—			930
Related party	—			7.2			32.5			(7.2		)	32.5
	—			713.8			295.7			(7.2		)	1,002.30
Expenses:
Operations and maintenance	—			31.3			73.3			—			104.6
General and administrative	—			10			83.5			—			93.5
Depreciation, amortization and accretion	—			26			141.9			—			167.9
	—			67.3			298.7			—			366
Other operating income (expense):
Gain (loss) on long-lived assets, net	—			(0.1		)	5.4			—			5.3
Goodwill impairment	—			—			(4.1		)	—			(4.1		)
Loss on contingent consideration	—			—			(31.4		)	—			(31.4		)
Operating income (loss)	—			(5.9		)	34.1			—			28.2
Earnings (loss) from unconsolidated affiliates, net	—			—			(0.1		)	—			(0.1		)
Interest and debt expense, net	(6.5		)	—			(71.4		)	—			(77.9		)
Other income, net	—			0.2			—			—			0.2
Equity in net income (loss) of subsidiary	(43.9		)	—			—			43.9			—
Income (loss) before income taxes	(50.4		)	(5.7		)	(37.4		)	43.9			(49.6		)
Provision for income taxes	0.2			0.1			0.7			—			1
Net income (loss)	(50.6		)	(5.8		)	(38.1		)	43.9			(50.6		)
Net (income) loss attributable to non-controlling partners in subsidiaries	—			—			57.3			—			57.3
Net income (loss) attributable to partners	$	(50.6	)	$	(5.8	)	$	19.2		$	43.9		$	6.7
Condensed Consolidating Statements of Comprehensive Income
Year Ended December 31, 2014
(in millions)
	Parent			Guarantor			Non-			Eliminations			Consolidated
				Subsidiaries			Guarantor
							Subsidiaries
Net income (loss)	$	(10.4	)	$	55		$	(40.8	)	$	(14.2	)	$	(10.4	)
Change in fair value of Suburban Propane Partners, LP units	(0.5		)	—			—			—			(0.5		)
Comprehensive income (loss)	$	(10.9	)	$	55		$	(40.8	)	$	(14.2	)	$	(10.9	)
Condensed Consolidating Statements of Comprehensive Income
Year Ended December 31, 2013
(in millions)
	Parent			Guarantor			Non-			Eliminations			Consolidated
				Subsidiaries			Guarantor
							Subsidiaries
Net income (loss)	$	(50.6	)	$	(5.8	)	$	(38.1	)	$	43.9		$	(50.6	)
Change in fair value of Suburban Propane Partners, LP units	(0.1		)	—			—			—			(0.1		)
Comprehensive income (loss)	$	(50.7	)	$	(5.8	)	$	(38.1	)	$	43.9		$	(50.7	)
Condensed Consolidating Statements of Cash Flows
Year Ended December 31, 2014
(in millions)
	Parent			Guarantor			Non-			Eliminations			Consolidated
				Subsidiaries			Guarantor
							Subsidiaries
Cash flows from operating activities:	$	(25.3	)	$	(14.6	)	$	322.9		$	—		$	283
Cash flows from investing activities:
Acquisitions, net of cash acquired	—			—			(19.5		)	—			(19.5		)
Purchases of property, plant and equipment	(3.8		)	(13.2		)	(407.0		)	—			(424.0		)
Investment in unconsolidated affiliates	35.8			—			(144.4		)	—			(108.6		)
Proceeds from the sale of assets	—			2.7			—			—			2.7
Proceeds from the sale of Tres Palacios	66.4			—			—			—			66.4
Capital contributions from consolidated affiliates, net	72.4			—			—			(72.4		)	—
Net cash provided by (used in) investing activities	170.8			(10.5		)	(570.9		)	(72.4		)	(483.0		)
Cash flows from financing activities:
Proceeds from the issuance of long-term debt	734			—			2,089.90			—			2,823.90
Principal payments on long-term debt	(746.2		)	—			(1,949.8		)	—			(2,696.0		)
Payments on capital leases	—			—			(3.2		)	—			(3.2		)
Payments for debt-related deferred costs	(1.8		)	—			(0.1		)	—			(1.9		)
Distributions paid to partners	(102.5		)	—			(72.4		)	72.4			(102.5		)
Distributions paid to non-controlling partners	—			—			(296.5		)	—			(296.5		)
Net proceeds from issuance of preferred equity of subsidiary	—			—			53.9			—			53.9
Net proceeds from issuance of CMLP Class A preferred units	—			—			430.5			—			430.5
Taxes paid for unit-based compensation vesting	—			(2.3		)	(1.6		)	—			(3.9		)
Change in intercompany balances	(25.4		)	25.4			—			—			—
Other	—			0.1			(0.8		)	—			(0.7		)
Net cash provided by (used in) financing activities	(141.9		)	23.2			249.9			72.4			203.6
Net change in cash	3.6			(1.9		)	1.9			—			3.6
Cash at beginning of period	0.1			2.4			2.7			—			5.2
Cash at end of period	$	3.7		$	0.5		$	4.6		$	—		$	8.8
Condensed Consolidating Statements of Cash Flows
Year Ended December 31, 2013
(in millions)
	Parent			Guarantor			Non-			Eliminations			Consolidated
				Subsidiaries			Guarantor
							Subsidiaries
Cash flows from operating activities:	$	(12.3	)	$	14.1		$	186.5		$	—		$	188.3
Cash flows from investing activities:
Acquisitions, net of cash acquired	—			5.9			(561.5		)	—			(555.6		)
Purchases of property, plant and equipment	—			(12.4		)	(334.6		)	—			(347.0		)
Investment in unconsolidated affiliates, net	—			—			(151.5		)	—			(151.5		)
Capital contributions from consolidated affiliates, net and other	20.7			0.1			11.1			(20.7		)	11.2
Net cash provided by (used in) investing activities	20.7			(6.4		)	(1,036.5		)	(20.7		)	(1,042.9		)
Cash flows from financing activities:
Proceeds from the issuance of long-term debt	394.1			—			2,072.80			—			2,466.90
Principal payments on long-term debt	(333.3		)	—			(1,634.3		)	—			(1,967.6		)
Distributions paid to partners	(68.4		)	—			(155.2		)	26.2			(197.4		)
Distributions paid to non-controlling partners	—			—			(204.5		)	—			(204.5		)
Net proceeds from the issuance of CMLP common units	—			—			714			—			714
Net proceeds from issuance of preferred equity of subsidiary	—			—			96.1			—			96.1
Change in intercompany balances	0.4			(0.4		)	—			—			—
Other	(1.1		)	(4.9		)	(36.3		)	(5.5		)	(47.8		)
Net cash provided by (used in) financing activities	(8.3		)	(5.3		)	852.6			20.7			859.7
Net increase in cash	0.1			2.4			2.6			—			5.1
Cash at beginning of period	—			—			0.1			—			0.1
Cash at end of period	$	0.1		$	2.4		$	2.7		$	—		$	5.2

Quarterly_Financial_Data_Unaud

Quarterly Financial Data (Unaudited)	12 Months Ended
	Dec. 31, 2014
Quarterly Financial Information Disclosure [Abstract]
Quarterly Financial Data	Quarterly Financial Data (Unaudited)
	Summarized unaudited quarterly financial data is presented below (in millions, except per unit information):
		Quarter Ended
		March 31				June 30			September 30			31-Dec
	2014
	Revenues	$	971.6			$	926.3		$	1,036.20		$	997.2
	Operating income (loss)	45.7				29.4			43			(0.2		)	(1)
	Earnings (loss) from unconsolidated affiliates, net	(0.1		)		(1.5		)	0.3			0.6
	Net income (loss)	13.2				(4.8		)	11.9			(30.7		)
	Net income (loss) attributable to partners	19.6				(4.4		)	2.8			38.4
	Net income (loss) per limited partner unit:
	Basic	$	0.11			$	(0.02	)	$	0.02		$	0.21
	Diluted	$	0.11			$	(0.02	)	$	0.02		$	0.21
	2013
	Revenues	$	72.4			$	118.9		$	427.2		$	808.2
	Operating income (loss)	15.7				7.8			15.8			(11.1		)	(2)
	Earnings (loss) from unconsolidated affiliates, net	—				—			(0.4		)	0.3
	Net income (loss)	3.9				(4.5		)	(7.9		)	(42.1		)
	Net income (loss) attributable to partners	5.1				1.6			(8.3		)	8.3
	Net income (loss) per limited partner unit:
	Basic(4)	$	0.13		(3)	$	0.03		$	(0.05	)	$	0.04
	Diluted(4)	$	0.13		(3)	$	0.03		$	(0.05	)	$	0.04
	-1	Includes goodwill, property, plant and equipment and intangible impairments of approximately $48.8 million, $13.2 million and $21.3 million, respectively. See Note 2 for a further discussion of our impairments recorded during 2014. In addition, include a gain of approximately $30.6 million on the sale of our interest in Tres Palacios. See Note 6, for a further discussion of our divestiture of Tres Palacios.
	-2	Includes a $31.4 million loss on contingent consideration which reflects the fair value of an earn-out premium associated with the original acquisition of our Antero assets. See Note 3 for a further discussion of this non-cash charge.
	-3	Basic and diluted net income for the quarter ended March 31, 2013, were calculated based on the presumption that the common and subordinated units issued to acquire Legacy Crestwood GP (the accounting predecessor) were outstanding for the entire period prior to the June 19, 2013 acquisition.
	-4	The accumulation of basic and diluted net income (loss) per limited partner unit does not total the amount for the year due to changes in ownership percentages throughout the year.

Schedule_I_Crestwood_Equity_Pa

Schedule I - Crestwood Equity Partners LP - Parent Only (Notes)	12 Months Ended
	Dec. 31, 2014
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
Schedule I - Crestwood Equity Partners LP (Formerly Inergy, L.P.) - Parent Only	Schedule I
	Crestwood Equity Partners LP
	Parent Only
	Condensed Balance Sheet
	(in millions)
		December 31,
		2014			2013
	Assets
	Current assets:
	Cash	$	3.7		$	0.1
	Accounts receivable - intercompany	3.2			—
	Total current assets	6.9			0.1
	Property, plant and equipment, net	2.5			—
	Intangible assets	1.7			—
	Investment in subsidiaries	5,971.20			5,927.10
	Total assets	$	5,982.30		$	5,927.20
	Liabilities and partners’ capital
	Current liabilities:
	Accrued expenses	$	1.9		$	2
	Current portion of long-term debt	3			2.2
	Total current liabilities	4.9			4.2
	Long-term debt, less current portion	380			393
	Other long-term liabilities	12.9			21.4
	Total partners’ capital	5,584.50			5,508.60
	Total liabilities and partners’ capital	$	5,982.30		$	5,927.20
	See accompanying notes.
	Schedule I
	Crestwood Equity Partners LP
	Parent Only
	Condensed Statement of Operations
	(in millions)
		Year Ended December 31,
		2014			2013			2012
	Revenues	$	—		$	—		$	—
	Expenses	8.5			—			21.3
	Gain on contingent consideration	—			—			6.8
	Operating income (loss)	(8.5		)	—			(14.5		)
	Interest and debt expense, net	(15.7		)	(6.5		)	—
	Equity in net income (loss) of subsidiaries	14.2			(43.9		)	38.9
	Income (loss) before income taxes	(10.0		)	(50.4		)	24.4
	Provision for income taxes	0.4			0.2			—
	Net income (loss)	(10.4		)	(50.6		)	24.4
	Net (income) loss attributable to non-controlling partners	—			—			(9.5		)
	Net income (loss) attributable to Crestwood Equity Partners LP	$	(10.4	)	$	(50.6	)	$	14.9
	See accompanying notes.
	Schedule I
	Crestwood Equity Partners LP
	Parent Only
	Condensed Statement of Comprehensive Income
	(in millions)
		Year Ended December 31,
		2014			2013			2012
	Net income (loss)	$	(10.4	)	$	(50.6	)	$	24.4
	Change in fair value of Suburban Propane Partners, LP units	(0.5		)	(0.1		)	—
	Comprehensive income (loss)	$	(10.9	)	$	(50.7	)	$	24.4
	See accompanying notes.
	Schedule I
	Crestwood Equity Partners LP
	Parent Only
	Condensed Statement of Cash Flows
	(in millions)
		Year Ended December 31,
		2014			2013			2012
	Cash flows from operating activities	$	(25.3	)	$	(12.3	)	$	—
Cash flows from investing activities	170.8			20.7			(146.2		)
Cash flows from financing activities:
Proceeds from the issuance of long-term debt	734			394.1			—
Principal payments on long-term debt	(746.2		)	(333.3		)	—
Payments for debt-related deferred costs	(1.8		)	—			—
Distributions paid to partners	(102.5		)	(68.4		)	(103.5		)
Contributions received	—			—			249.7
Change in intercompany balances	(25.4		)	0.4			—
Other	—			(1.1		)	—
Net cash provided by (used in) financing activities	(141.9		)	(8.3		)	146.2
Net change in cash	3.6			0.1			—
Cash at beginning of period	0.1			—			—
Cash at end of period	$	3.7		$	0.1		$	—
See accompanying notes.
Schedule I
Crestwood Equity Partners LP
Parent Only
Notes to Condensed Financial Statements
Note 1. Basis of Presentation
In the parent-only financial statements, our investment in subsidiaries is stated at cost plus equity in undistributed earnings of subsidiaries since the date of acquisition.  Our share of net income of our unconsolidated subsidiaries is included in consolidated income using the equity method.  The parent-only financial statements should be read in conjunction with our consolidated financial statements.
The condensed statement of cash flows for the year ended December 31, 2013 has been corrected for certain errors in presentation. There was no impact to our condensed statement of cash flows for the year ended December 31, 2013. The following table summarizes the impact of the adjustments (in millions):
	As Adjusted			As Previously Reported
Cash flows from operating activities:	$	(12.3	)	$	—
Cash flows from investing activities:	20.7			76
Cash flows from financing activities:
Proceeds from the issuance of long-term debt	394.1			—
Principal payments on long-term debt	(333.3		)	—
Distributions paid to partners	(68.4		)	(76.0		)
Distributions paid to non-controlling partners	—			—
Change in intercompany balances	0.4			—
Other	(1.1		)	0.1
Net cash used in financing activities	$	(8.3	)	$	(75.9	)
Note 2. Distributions
During the years ended December 31, 2014, 2013 and 2012, we received cash distributions from Crestwood Midstream Partners LP of approximately $72.4 million, $26.2 million and $25.8 million.

Schedule_II_Crestwood_Equity_P

Schedule II - Crestwood Equity Parnters LP - Valuation and Qualifying Accounts (Notes)	12 Months Ended
	Dec. 31, 2014
Valuation and Qualifying Accounts [Abstract]
Schedule of Valuation and Qualifying Accounts Disclosure [Text Block]	Schedule II
	Crestwood Equity Partners LP
	Valuation and Qualifying Accounts
	For the Years Ended December 31, 2014 and 2013
	(in millions)
		Balance at		Charged			Other		Deductions		Balance
		beginning		to costs and			Additions		(write-offs)		at end
		of period		expenses							of period
	Allowance for doubtful accounts(1)
	2014	$	0.1	$	—		$	—	$	—	$	0.1
	2013	—		(1.1		)	1.2		—		0.1
	(1) There was no activity for the year ended December 31, 2012.

Basis_of_Presentation_and_Summ1

Basis of Presentation and Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2014
Accounting Policies [Abstract]
Use of Estimates	Use of Estimates
	The preparation of our consolidated financial statements in conformity with GAAP requires the use of estimates and assumptions that affect the amounts we report as assets, liabilities, revenues and expenses and our disclosures in these consolidated financial statements. Actual results can differ from those estimates.
Cash	Cash
	We consider all highly liquid investments with an original maturity of less than three months to be cash.
Inventory	Inventory
	Inventory for our NGL and crude services operations and our storage and transportation operations are stated at the lower of cost or market and are computed predominantly using the average cost method.
Property, Plant and Equipment	Property, Plant and Equipment
	Property, plant and equipment is recorded at is original cost of construction or, upon acquisition, at the fair value of the assets acquired. For assets we construct, we capitalize direct costs, such as labor and materials, and indirect costs, such as overhead and interest. We capitalize major units of property replacements or improvement and expense minor items. Depreciation is computed by the straight-line method over the estimated useful lives of the assets, as follows:
		Years
	Gathering systems and pipelines	20
	Facilities and equipment	20 – 25
	Buildings, rights-of-way and easements	20 – 40
	Office furniture and fixtures	5 – 10
	Vehicles	5
	We deplete salt deposits included in our property, plant and equipment utilizing the unit of production method.
	When we retire property, plant and equipment, we charge accumulated depreciation for the original costs of the assets in addition to the cost to remove, sell or dispose of the assets, less their salvage value.
	We evaluate our long-lived assets for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. If such events or changes in circumstances are present, a loss is recognized if the carrying value of the asset is in excess of the sum of the undiscounted cash flows expected to result from the use of the asset and its eventual disposition. An impairment loss is measured as the amount by which the carrying amount of the asset exceeds the fair value of the asset, which is based on discounted cash flow projections, which is a Level 3 fair value measurement. Based on this evaluation, during the year ended December 31, 2014, we recorded a $13.2 million impairment in gain (loss) on long-lived assets in our consolidated statements of operations related to the property, plant and equipment of our gathering and processing assets located in the Granite Wash, which resulted from an announcement during the fourth quarter of 2014 by our major customer of those assets that they would cease any substantial drilling in the Granite Wash in the near future given current and future anticipated market conditions related to natural gas, which negatively impacted our future cash flows related to these operations. We had approximately $20.2 million of property, plant and equipment related to our gathering and processing operations located in the Granite Wash as of December 31, 2014, which represents the fair value of those assets based on its projected cash flows over the useful lives of the assets of 17 years and a discount rate of 9.0%, which are Level 3 fair value measurements. We did not record any impairments of our long-lived assets during the years ended December 31, 2013 and 2012 based on this evaluation.
Identifiable Intangible Assets	Identifiable Intangible Assets
	Our identifiable intangible assets consist of customer accounts, covenants not to compete, trademarks, certain revenue contracts and deferred financing costs. Customer accounts, covenants not to compete, trademarks and certain of our revenue contracts have arisen from acquisitions. We amortize certain of our revenue contracts based on the projected cash flows associated with these contracts if the projected cash flows are reliably determinable, otherwise we amortize our revenue contracts on a straight-line basis.  Deferred financing costs represent financing costs incurred in obtaining financing and are being amortized over the term of the related debt using a method which approximates the effective interest method and has a weighted average life of six years. We recognize acquired intangible assets separately if the benefit of the intangible asset is obtained through contractual or other legal rights, or if the intangible asset can be sold, transferred, licensed, rented or exchanged, regardless of the acquirer's intent to do so. For the year ended December 31, 2014, we recorded a $21.3 million impairment of our intangible assets in gain (loss) on long-lived assets in our consolidated statements of operations. This impairment was based on the intangible assets’ fair value, estimated primarily by utilizing discounted cash flow projections, which is a Level 3 fair value measurement.  This impairment was primarily related to a full impairment of our intangible assets associated with our gathering and processing operations located in the Granite Wash. This impairment resulted from an announcement in the fourth quarter of 2014 by our major customer of those assets that they would cease any substantial drilling in the Granite Wash in the near future given current and future anticipated market conditions related to natural gas in
Goodwill	Identifiable Intangible Assets
	Our identifiable intangible assets consist of customer accounts, covenants not to compete, trademarks, certain revenue contracts and deferred financing costs. Customer accounts, covenants not to compete, trademarks and certain of our revenue contracts have arisen from acquisitions. We amortize certain of our revenue contracts based on the projected cash flows associated with these contracts if the projected cash flows are reliably determinable, otherwise we amortize our revenue contracts on a straight-line basis.  Deferred financing costs represent financing costs incurred in obtaining financing and are being amortized over the term of the related debt using a method which approximates the effective interest method and has a weighted average life of six years. We recognize acquired intangible assets separately if the benefit of the intangible asset is obtained through contractual or other legal rights, or if the intangible asset can be sold, transferred, licensed, rented or exchanged, regardless of the acquirer's intent to do so. For the year ended December 31, 2014, we recorded a $21.3 million impairment of our intangible assets in gain (loss) on long-lived assets in our consolidated statements of operations. This impairment was based on the intangible assets’ fair value, estimated primarily by utilizing discounted cash flow projections, which is a Level 3 fair value measurement.  This impairment was primarily related to a full impairment of our intangible assets associated with our gathering and processing operations located in the Granite Wash. This impairment resulted from an announcement in the fourth quarter of 2014 by our major customer of those assets that they would cease any substantial drilling in the Granite Wash in the near future given current and future anticipated market conditions related to natural gas in the Granite Wash.
	Certain intangible assets are amortized on a straight-line basis over their estimated economic lives, as follows:
		Weighted-Average
		Life
		(years)
	Customer accounts	22
	Covenants not to compete	5
	Trademarks	6
Investment in Unconsolidated Affiliate	Investment in Unconsolidated Affiliates
	We evaluate our equity method investments for impairment when events or circumstances indicate that the carrying value of the equity method investment may be impaired. If an event occurs, we evaluate the recoverability of our carrying value based on the fair value of the investment. If an impairment is indicated, or if we decide to sell an investment in unconsolidated affiliate, we adjust the carrying values of the asset downward, if necessary, to their estimated fair values. Our fair value estimates are generally based on assumptions market participants would use, including marketing data obtained through the sales process.
Asset Retirement Obligations	Asset Retirement Obligations
	An asset retirement obligation (ARO) is an estimated liability for the cost to retire a tangible asset. We record a liability for legal or contractual obligations to retire our long-lived assets associated with right-of-way contracts we hold and our facilities whether owned or leased. We record a liability in the period the obligation is incurred and estimable. An ARO is initially recorded at its estimated fair value with a corresponding increase to property, plant and equipment. This increase in property, plant and equipment is then depreciated over the useful life of the asset to which that liability relates. An ongoing expense is recognized for changes in the fair value of the liability as a result of the passage of time, which we record as depreciation, amortization and accretion expense on our consolidated statements of operations. The fair value of certain AROs could not be determined as the settlement dates (or range of dates) associated with these assets were not estimable. At December 31, 2014 and 2013, our AROs were reflected in other long-term liabilities on our consolidated balance sheets. See Note 5 for a further discussion of our AROs.
Revenue Recognition	Revenue Recognition
	We gather, treat, compress, store, transport and sell various commodities (including crude oil, natural gas, NGLs and water) pursuant to fixed-fee and percent-of-proceeds contracts. We recognize revenues for these services and products when all of the following criteria are met:
	• services have been rendered or products delivered or sold;
	• persuasive evidence of an exchange arrangement exists;
	• the price for services is fixed or determinable; and
	• collectability is reasonably assured.
	For fixed-fee contracts, we recognize revenues based on the volume of crude oil, natural gas or produced water gathered, processed and treated or compressed, as applicable. For percent-of-proceeds contracts, we recognize revenues based on the value of products sold to third parties.
	Sales of crude oil, NGLs and salt are recognized at the time product is shipped or delivered to the customer depending on the sales terms. NGL processing and fractionation fees are recognized upon delivery of the product. Revenues from the COLT Hub are recognized when the contractual services are provided, such as loading of customer rail cars. Revenues from storage and transportation contracts are recognized during the period in which the storage and transportation services are provided, such as providing storage and transportation services during the period a firm service contract is in place. We record deferred revenue when we receive amounts from our customers but have not met the criteria listed above. We recognize deferred revenue in our consolidated statements of operations when the criteria has been met and all services have been rendered. At December 31, 2014 and 2013
	, we had deferred revenue of approximately
	$12.2 million and $2.1 million, which is reflected in accrued expenses and other liabilities on our consolidated balance sheets.
Credit Risk and Concentrations	Credit Risk and Concentrations
	Inherent in our contractual portfolio are certain credit risks. Credit risk is the risk of loss from nonperformance by suppliers, customers or financial counterparties to a contract. We take an active role in managing credit risk and have established control procedures, which are reviewed on an ongoing basis. We attempt to minimize credit risk exposure through credit policies and periodic monitoring procedures as well as through customer deposits, letters of credit and entering into netting agreements that allow for offsetting counterparty receivable and payable balances for certain financial transactions, as deemed appropriate.
Income Taxes	Income Taxes
	We are a master limited partnership. Partnerships are generally not subject to federal income tax, although publicly-traded partnerships are treated as corporations for federal income tax purposes and therefore are subject to federal income tax, unless the partnership generates at least 90% of its gross income from qualifying sources. If the qualifying income requirement is satisfied, the publicly-traded partnership will be treated as a partnership for federal income tax purposes. We satisfy the qualifying income requirement and are treated as a partnership for federal and state income tax purposes. Our consolidated earnings are included in the federal and state income tax returns of our partners. However, legislation in certain states allows for taxation of partnerships, and as such, certain state taxes have been included in our accompanying financial statements as income taxes due to the nature of the tax in those particular states as discussed below. In addition, federal and state income taxes are provided on the earnings of the subsidiaries incorporated as taxable entities. We are required to recognize deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the financial statements or tax returns. Under this method, deferred tax assets and liabilities are determined based on the differences between the financial reporting and tax basis of assets and liabilities using expected rates in effect for the year in which the differences are expected to reverse.
	We are responsible for the Texas Margin tax computed on the Texas franchise tax returns. The margin tax qualifies as an income tax under GAAP, which requires us to recognize the impact of this tax on the temporary differences between the financial statement assets and liabilities and their tax basis attributable to such tax.
	Net earnings for financial statement purposes may differ significantly from taxable income reportable to unitholders as a result of differences between the tax basis and the financial reporting basis of assets and liabilities and the taxable income allocation requirements under the partnership agreement.
Environmental Costs and Other Contingencies	Environmental Costs and Other Contingencies
	We recognize liabilities for environmental and other contingencies when there is an exposure that indicates it is both probable that a liability has been incurred and the amount of loss can be reasonably estimated. Where the most likely outcome of a contingency can be reasonably estimated, we accrue a liability for that amount. Where the most likely outcome cannot be estimated, a range of potential losses is established and if no one amount in that range is more likely than any other, the low end of range is accrued.
	We record liabilities for environmental contingencies at their undiscounted amounts on our consolidated balance sheets as accrued expenses and other liabilities when environmental assessments indicate that remediation efforts are probable and costs can be reasonably estimated. Estimates of our liabilities are based on currently available facts and presently enacted laws and regulations, taking into consideration the likely effects of other societal and economic factors. These estimates are subject to revision in future periods based on actual costs or new circumstances. We capitalize costs that benefit future periods and recognize a current period charge in operations and maintenance expenses when clean-up efforts do not benefit future periods.
	We evaluate potential recoveries of amounts from third parties, including insurance coverage, separately from our liability. Recovery is evaluated based on the solvency of the third party, among other factors. When recovery is assured, we record and report an asset separately from the associated liability on our consolidated balance sheet.
Price Risk Management Activities	Price Risk Management Activities
	We utilize certain derivative financial instruments to (i) manage our exposure to commodity price risk, specifically, the related change in the fair value of inventory, as well as the variability of cash flows related to forecasted transactions; (ii) ensure the availability of adequate physical supply of commodity; and (iii) manage our exposure to the interest rate risk associated with fixed and variable rate borrowings. We record all derivative instruments on the balance sheet at their fair values as either assets or liabilities measured at fair value. Changes in the fair value of these derivative financial instruments are recorded through current earnings.
	We did not have any derivatives identified as fair value hedges for accounting purposes or any derivatives designated as cash flow hedges for the years ended December 31, 2014, 2013 or 2012.
Unit-Based Compensation	Unit-Based Compensation
	Long-term incentive awards are granted under the Crestwood Equity and Crestwood Midstream incentive plans. Unit-based compensation awards consist of restricted units that are valued at the closing market price of CEQP's or CMLP's common units on the date of grant, which reflects the fair value of such awards. For those awards that are settled in cash, the associated liability is remeasured at every balance sheet date through settlement, such that the vested portion of the liability is adjusted to reflect its revised fair value through compensation expense. We generally recognize the expense associated with the award over the vesting period.
	Prior to the Crestwood Merger, Legacy Crestwood issued phantom units under its Fourth Amended and Restated 2007 Equity Plan (2007 Equity Plan). The 2007 Equity Plan was terminated in conjunction with the Crestwood Merger. See Note 13 for a further discussion of our long-term incentive plans.

Basis_of_Presentation_and_Summ2

Basis of Presentation and Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2014
Accounting Policies [Abstract]
Estimated Useful Lives Of Property, Plant And Equipment	Depreciation is computed by the straight-line method over the estimated useful lives of the assets, as follows:
		Years
	Gathering systems and pipelines	20
	Facilities and equipment	20 – 25
	Buildings, rights-of-way and easements	20 – 40
	Office furniture and fixtures	5 – 10
	Vehicles	5
Intangible Assets, Useful life	Certain intangible assets are amortized on a straight-line basis over their estimated economic lives, as follows:
		Weighted-Average
		Life
		(years)
	Customer accounts	22
	Covenants not to compete	5
	Trademarks	6
	Intangible assets consisted of the following at December 31, 2014 and 2013 (in millions):
		December 31,
		2014		2013
	Customer accounts	$	583.7	$	576.9
	Covenants not to compete	9.6		7
	Gas gathering, compression and processing contracts	730.2		750.2
	Acquired storage contracts	29		43.5
	Trademarks	32.2		33.5
	Deferred financing costs	57.2		55.3
		1,441.90		1,466.40
	Less: accumulated amortization	210.6		106
	Total intangible assets, net	$	1,231.30	$	1,360.40
	The following table summarizes the total of accumulated amortization of intangible assets by the type of intangible asset at December 31, 2014 and 2013:
		December 31,
		2014		2013
	Customer accounts	$	72.5	$	18.7
	Covenants not to compete	3.2		1
	Gas gathering, compression and processing contracts	98		67.3
	Acquired storage contracts	12.7		8.6
	Trademarks	6.7		2.3
	Deferred financing costs	17.5		8.1
	Total accumulated amortization	$	210.6	$	106

Acquisitions_Tables

Acquisitions (Tables)	12 Months Ended
	Dec. 31, 2014
Business Acquisition [Line Items]
Business Acquisition, Pro Forma Information	The following table presents unaudited pro forma consolidated revenues, net income and net income per limited partner unit as if the Legacy Inergy reverse acquisition and the Arrow Acquisition had been included in our consolidated results for the year ended December 31, 2012 and for the entire year ended December 31, 2013 (in millions, except per unit information). All other acquisitions were immaterial in consolidation.
		Year Ended December 31,
		2013		2012 (1)
	Revenues	$	3,449.30	$	2,267.20
	Net income	$	3.9	$	49.8
	Net income per limited partner unit(2):
	Basic	$	0.04	$	0.31
	Diluted	$	0.04	$	0.29
	-1	The year ended December 31, 2012 has also been adjusted to reflect the contribution of Inergy, L.P.'s retail operations to Suburban Propane Partners on August 1, 2012 and the subsequent distribution on September 14, 2012 of 99% of the Suburban Propane Partners LP units acquired in the contribution as if that contribution and subsequent distribution had been removed from the consolidated results of operations at the beginning of each period presented.
	(2) Basic and diluted net income per limited partner unit for the year ended December 31, 2012 were computed based on the presumption that the common and subordinated units issued to acquire Legacy Crestwood GP (the accounting predecessor) were outstanding for the entire period prior to the June 19, 2013 acquisition.
Inergy Midstream
Business Acquisition [Line Items]
Schedule of Recognized Identified Assets Acquired and Liabilities Assumed	The following table summarizes the final valuation of the assets acquired and liabilities assumed at the merger date (in millions):
	Current assets	$	224.5
	Property, plant and equipment	2,088.10
	Intangible assets	337.5
	Other assets	12.7
	Total identifiable assets acquired	2,662.80
	Current liabilities	207.6
	Long-term debt	1,079.30
	Other long-term liabilities	146.6
	Total liabilities assumed	1,433.50
	Net identifiable assets acquired	1,229.30
	Goodwill	2,134.80
	Net assets acquired	$	3,364.10
Arrow Midstream Holdings, LLC
Business Acquisition [Line Items]
Schedule of Recognized Identified Assets Acquired and Liabilities Assumed	The following table summarizes the final valuation of the assets acquired and liabilities assumed at the acquisition date (in millions):
	Current assets	$	192.7
	Property, plant and equipment	400.5
	Intangible assets	323.4
	Other assets	19.5
	Total identifiable assets acquired	936.1
	Current liabilities	215.8
	Assets retirement obligations	1.2
	Other long-term liabilities	3.7
	Total liabilities assumed	220.7
	Net identifiable assets acquired	715.4
	Goodwill	45.9
	Net assets acquired	$	761.3
Devon
Business Acquisition [Line Items]
Schedule of Recognized Identified Assets Acquired and Liabilities Assumed	The final purchase price allocation is as follows (in millions):
	Cash	$	87.9
	Total purchase price	$	87.9
	Purchase price allocation:
	Property, plant and equipment	$	88.6
	Total assets	88.6
	Asset retirement obligation	0.5
	Environmental liability	0.2
	Total liabilities	0.7
	Total	$	87.9
EMAC
Business Acquisition [Line Items]
Schedule of Recognized Identified Assets Acquired and Liabilities Assumed	The final purchase price allocation is as follows (in millions):
	Cash	$	95
	Total purchase price	$	95
	Purchase price allocation:
	Property, plant and equipment	$	53.4
	Intangible assets	33.9
	Goodwill	8.6
	Total assets	95.9
	Asset retirement obligation	0.8
	Environmental liability	0.1
	Total liabilities	0.9
	Total	$	95

Certain_Balance_Sheet_Informat1

Certain Balance Sheet Information (Tables)	12 Months Ended
	Dec. 31, 2014
Balance Sheet Related Disclosures [Abstract]
Inventories	Inventory consisted of the following at December 31, 2014 and 2013 (in millions):
		December 31,
		2014		2013
	NGLs	$	37.5	$	66.9
	Parts, supplies and other	9.1		6.7
	Total inventory	$	46.6	$	73.6
Property, Plant And Equipment	Property, plant and equipment consisted of the following at December 31, 2014 and 2013 (in millions):
		December 31,
		2014		2013
	Gathering systems and pipelines	$	1,410.90	$	1,473.40
	Facilities and equipment	1,648.30		1,186.50
	Buildings, land, rights-of-way, storage contracts and easements	841.5		814.7
	Vehicles	45.2		35.8
	Construction in process	156.5		365.8
	Base gas	37.5		102
	Salt deposits	120.5		120.5
	Office furniture and fixtures	13.5		10
		4,273.90		4,108.70
	Less: accumulated depreciation and depletion	380.1		203.4
	Total property, plant and equipment, net	$	3,893.80	$	3,905.30
Intangible Assets	Certain intangible assets are amortized on a straight-line basis over their estimated economic lives, as follows:
		Weighted-Average
		Life
		(years)
	Customer accounts	22
	Covenants not to compete	5
	Trademarks	6
	Intangible assets consisted of the following at December 31, 2014 and 2013 (in millions):
		December 31,
		2014		2013
	Customer accounts	$	583.7	$	576.9
	Covenants not to compete	9.6		7
	Gas gathering, compression and processing contracts	730.2		750.2
	Acquired storage contracts	29		43.5
	Trademarks	32.2		33.5
	Deferred financing costs	57.2		55.3
		1,441.90		1,466.40
	Less: accumulated amortization	210.6		106
	Total intangible assets, net	$	1,231.30	$	1,360.40
	The following table summarizes the total of accumulated amortization of intangible assets by the type of intangible asset at December 31, 2014 and 2013:
		December 31,
		2014		2013
	Customer accounts	$	72.5	$	18.7
	Covenants not to compete	3.2		1
	Gas gathering, compression and processing contracts	98		67.3
	Acquired storage contracts	12.7		8.6
	Trademarks	6.7		2.3
	Deferred financing costs	17.5		8.1
	Total accumulated amortization	$	210.6	$	106
Schedule of Intangible Assets, Future Amortization Expense	Estimated amortization of our intangible assets for the next five years is as follows (in millions):
	Year Ending
	December 31,
	2015	$	115.1
	2016	101.2
	2017	87.5
	2018	73.9
	2019	65.5
Schedule of Accrued Liabilities	Accrued expenses and other liabilities consisted of the following at December 31, 2014 and 2013 (in millions):
		December 31,
		2014		2013
	Accrued expenses	$	52.5	$	40.3
	Accrued property taxes	2.2		9.4
	Accrued product purchases payable	0.7		1.6
	Tax payable	1.6		14.8
	Interest payable	23.5		16.7
	Accrued additions to property, plant and equipment	20		58.2
	Commitments and contingent liabilities (Note 15)	40		31.4
	Capital leases	1.9		2.6
	Deferred revenue	12.2		2.1
	Total accrued expenses and other liabilities	$	154.6	$	177.1

Asset_Retirement_Obligations_T

Asset Retirement Obligations (Tables)	12 Months Ended
	Dec. 31, 2014
Asset Retirement Obligation Disclosure [Abstract]
Schedule of Asset Retirement Obligations	The following table presents the changes in the net asset retirement obligations for the years ended December 31, 2014 and 2013 (in millions):
		December 31,
		2014		2013
	Net asset retirement obligation at January 1	$	15.1	$	14
	Liabilities incurred	4.6		—
	Acquisitions	1.2		—
	Accretion expense	1.1		0.8
	Changes in estimate	1.8		0.3
	Net asset retirement obligation at December 31	$	23.8	$	15.1

Risk_Management_Tables

Risk Management (Tables)	12 Months Ended
	Dec. 31, 2014
Risk Management - Notional Amounts and Terms of Companys Derivative Financial Instruments [Abstract]
Notional Amounts And Terms Of Company's Derivative Financial Instruments	The notional amounts and terms of our derivative financial instruments include the following at December 31, 2014 and 2013(in millions):
		31-Dec-14		31-Dec-13
		Fixed Price	Fixed Price	Fixed Price	Fixed Price
		Payor	Receiver	Payor	Receiver
	Propane, crude and heating oil (barrels)	6.8	8.4	5.6	6.8
	Natural gas (MMBTU’s)	0.2	0.1	—	—

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2014
Fair Value, Assets, Liabilities and Stockholders' Equity Measured on Recurring Basis [Abstract]
Schedule of Carrying Values and Estimated Fair Values of Debt Instruments	The following table reflects the carrying value and fair value of the senior notes (in millions):
		December 31, 2014				December 31, 2013
		Carrying Amount		Fair		Carrying Amount		Fair
				Value				Value
	CEQP Senior Notes	$	11.4	$	11.6	$	11.4	$	11.6
	Crestwood Midstream 2019 Senior Notes	$	351	$	360.5	$	351.2	$	379.3
	Crestwood Midstream 2020 Senior Notes	$	504	$	481.6	$	504.7	$	513.8
	Crestwood Midstream 2022 Senior Notes	$	600	$	568.5	$	600	$	617.3
Assets And Liabilities Measured At Fair Value On Recurring Basis	The following tables set forth by level within the fair value hierarchy, our financial instruments that were accounted for at fair value on a recurring basis at December 31, 2014 and 2013 (in millions):
		31-Dec-14
		Fair Value of Derivatives
		Level 1		Level 2		Level 3		Total		Netting			Total
										Agreements(1)
	Assets
	Assets from price risk management	$	0.5	$	146.7	$	—	$	147.2	$	(67.4	)	$	79.8
	Suburban Propane Partners, L.P. units	6.1		—		—		6.1		—			6.1
	Total assets at fair value	$	6.6	$	146.7	$	—	$	153.3	$	(67.4	)	$	85.9
	Liabilities
	Liabilities from price risk management	$	1.6	$	99.2	$	—	$	100.8	$	(75.4	)	$	25.4
	Interest rate swaps	—		1.6		—		1.6		—			1.6
	Total liabilities at fair value	$	1.6	$	100.8	$	—	$	102.4	$	(75.4	)	$	27
		31-Dec-13
		Fair Value of Derivatives
		Level 1		Level 2		Level 3		Total		Netting			Total
										Agreements(1)
	Assets
	Assets from price risk management	$	0.3	$	27.7	$	—	$	28	$	(13.5	)	$	14.5
	Suburban Propane Partners, L.P. units	6.7		—		—		6.7		—			6.7
	Total assets at fair value	$	7	$	27.7	$	—	$	34.7	$	(13.5	)	$	21.2
	Liabilities
	Liabilities from price risk management	$	0.1	$	39.5	$	—	$	39.6	$	(4.7	)	$	34.9
	Interest rate swaps	—		4.3		—		4.3		—			4.3
	Total liabilities at fair value	$	0.1	$	43.8	$	—	$	43.9	$	(4.7	)	$	39.2
	(1) Amounts represent the impact of legally enforceable master netting agreements that allow us to settle positive and negative positions as well as cash collateral held or placed with the same counterparties.

LongTerm_Debt_Tables

Long-Term Debt (Tables)	12 Months Ended
	Dec. 31, 2014
Text Block [Abstract]
Components Of Long-Term Debt	Long-term debt consisted of the following at December 31, 2014 and 2013, (in millions):
		December 31,		December 31,
		2014		2013
	CEQP Credit Facility	$	369	$	381
	CEQP Senior Notes	11.4		11.4
	Crestwood Midstream Revolver	555		414.9
	Crestwood Midstream 2019 Senior Notes	350		350
	Premium on Crestwood Midstream 2019 Senior Notes	1		1.2
	Crestwood Midstream 2020 Senior Notes	500		500
	Fair value adjustment of Crestwood Midstream 2020 Senior Notes	4		4.7
	Crestwood Midstream 2022 Senior Notes	600		600
	Other	6.1		2.8
	Total debt	2,396.50		2,266.00
	Less: current portion	3.7		5.1
	Total long-term debt	$	2,392.80	$	2,260.90
Schedule of Maturities of Long-term Debt	The aggregate maturities of principal amounts on our outstanding long-term debt and other notes payable as of December 31, 2014 for the next five years and in total thereafter are as follows (in millions):
	2015	$	3.7
	2016	367.9
	2017	0.9
	2018	566.1
	2019	350.9
	Thereafter	1,102.00
	Total debt	$	2,391.50

Income_Taxes_Tables

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Schedule of Components of Income Tax Expense (Benefit)	The provision for income taxes for the years ended December 31, 2014, 2013, and 2012 consisted of the following (in millions):
		Year Ended December 31,
		2014			2013			2012
	Current:
	Federal	$	5		$	2.5		$	—
	State	1.3			1.3			1.2
	Total current	6.3			3.8			1.2
	Deferred:
	Federal	(5.3		)	(2.5		)	—
	State	0.1			(0.3		)	—
	Total deferred	(5.2		)	(2.8		)	—
	Provision for income taxes	$	1.1		$	1		$	1.2
Schedule of Deferred Tax Assets and Liabilities	Components of the deferred income taxes at December 31, 2014 and 2013 are as follows (in millions).
		December 31,
		2014			2013
	Deferred tax liability:
	Basis difference in stock of acquired company	$	(12.0	)	$	(17.2	)
	Total deferred tax liability	$	(12.0	)	$	(17.2	)

Partners_Capital_Tables

Partners' Capital (Tables)	12 Months Ended
	Dec. 31, 2014
Partners' Capital [Abstract]
Schedule of Limited Partners' Capital Account by Class	The table below presents limited partner unit issuances by Legacy Crestwood, Inergy Midstream and Crestwood Midstream.
	Issuer		Issuance Date		Units			Per Unit				Per Unit		Net
								Gross Price				Net Price (1)		Proceeds
	Legacy Crestwood		January 13, 2012		3,500,000			$	30.73			$	29.5	$	103.1
	Legacy Crestwood		July 25, 2012		4,600,000		(2)	26				24.97		114.4
	Legacy Crestwood		March 22, 2013		5,175,000		(3)	23.9				23		118.5
	Inergy Midstream		September 13, 2013		11,773,191		(4)	22.5				21.69		255.2
	Crestwood Midstream		October 23, 2013		16,100,000		(5)	N/A				21.19		340.3
	(1)	Price is net of underwriting discounts.
	(2)	Includes 600,000 units that were issued in August 2012.
	(3)	Includes 675,000 units that were issued in April 2013.
	(4)	Includes 773,191 units that were issued on October 7, 2013.
	(5)	Includes 2,100,000 units that were issued on October 30, 2013.
	The components of net income (loss) attributable to non-controlling partners on our consolidated statements of operations for the years ended December 31, 2014, 2013 and 2012 are as follows (in millions):
		Year Ended December 31,
		2014				2013				2012
	Crestwood Midstream limited partner interests	$	(100.8	)		$	(62.2	)		$	9.5
	Crestwood Niobrara preferred interests	16.8				4.9				—
	Crestwood Midstream Class A preferred units	17.2				—				—
	Net income (loss) attributable to non-controlling partners	$	(66.8	)		$	(57.3	)		$	9.5
Schedule of Distributions Made to Members or Limited Partners, by Distribution	A summary of our limited partner quarterly cash distributions for the years ended December 31, 2014 and 2013 (subsequent to the June 19, 2013 reverse acquisition) is presented below:
	Record Date		Payment Date		Per Unit Rate				Cash Distributions
									(in millions)
	2014
	February 7, 2014		February 14, 2014		$	0.1375			$	25.6
	May 8, 2014		May 15, 2014		$	0.1375			25.7
	August 7, 2014		August 14, 2014		$	0.1375			25.6
	November 7, 2014		November 14, 2014		$	0.1375			25.6
									$	102.5
	2013
	August 7, 2013		August 14, 2013		$	0.13			$	22.3
	November 7, 2013		November 14, 2013		$	0.135			25
									$	47.3

Equity_Plans_Tables

Equity Plans (Tables)	12 Months Ended
	Dec. 31, 2014
Equity [Abstract]
Disclosure of Share-based Compensation Arrangements by Share-based Payment Award	The following table summarizes information regarding restricted unit activity during the year ended December 31, 2014:
			Units			Weighted-Average Grant Date Fair Value
	Unvested - January 1, 2014		493,543			$	13.96
	Vested - restricted units		(449,936	)		$	13.97
	Granted - restricted units		1,377,461			$	13.23
	Forfeited		(105,188	)		$	13.73
	Unvested - December 31, 2014		1,315,880			$	13.21
	The following table summarizes information regarding restricted unit activity during the year ended December 31, 2014:
			Units			Weighted-Average Grant Date Fair Value
	Unvested - January 1, 2014		250,557			$	22.13
	Vested - restricted units		(208,361	)		$	22.15
	Granted - restricted units		871,078			$	23.25
	Forfeited		(78,478	)		$	23.33
	Unvested - December 31, 2014		834,796			$	23.18
	The following table summarizes information regarding phantom and restricted unit activity:
		Payable In Cash						Payable In Units
		Units			Weighted-			Units		Weighted-
					Average Grant					Average Grant
					Date Fair					Date Fair
					Value					Value
	Unvested - December 31, 2012	8,312			$	26.45		221,992		$	28.35
	Vested - phantom units	(7,958	)		$	26.48		(329,825	)	$	26.69
	Vested - restricted units	—			$	—		(74,760	)	$	25.6
	Granted - phantom units	—			$	—		161,807		$	24.33
	Granted - restricted units	—			$	—		27,900		$	24.86
	Canceled - phantom units	(354	)		$	25.81		(7,114	)	$	27.96
	Unvested - December 31, 2013	—			$	—		—		$	—

Commitments_and_Contingencies_

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Schedule of Future Minimum Rental Payments for Operating Leases	Future minimum lease payments under noncancelable operating leases for the next five years ending December 31 and in total thereafter consist of the following (in millions):
	Year Ending
	December 31,
	2015	$	16.9
	2016	15.5
	2017	12.9
	2018	11
	2019	9.9
	Thereafter	17.5
	Total minimum lease payments	$	83.7
Schedule of Future Minimum Lease Payments for Capital Leases	Future minimum lease payments related to our capital leases at December 31, 2014 are as follows (in millions):
	Year Ending
	December 31,
	2015	$	2.2
	2016	1.6
	2017	1.2
	2018	0.4
	Total payments	5.4
	Imputed interest	(0.1		)
	Present value of future payments	$	5.3

Related_Party_Transactions_Tab

Related Party Transactions (Tables)	12 Months Ended
	Dec. 31, 2014
Related Party Transactions [Abstract]
Schedule of Related Party Transactions	The following table shows revenues, costs of goods sold and general and administrative expenses from our affiliates for the years December 31, 2014, 2013 and 2012 (in millions):
		Year Ended December 31,
		2014 (1)		2013		2012
	Gathering and processing revenues	$	3	$	74.9	$	113.7
	Gathering and processing costs of product/services sold(2)	$	42.2	$	32.5	$	15.2
	General and administrative expenses	$	0.5	$	25.3	$	19.5
	(1) Concurrent with the Crestwood Merger, Quicksilver Resources Inc. (Quicksilver) is no longer a related party, and as a result our transactions with
	Quicksilver subsequent to June 19, 2013, are now considered non-affiliated transactions.
	(2) Represents natural gas purchases from Sabine Oil and Gas.
Schedule of Related Party Receivables and Payables	The following table shows accounts receivable and accounts payable from our affiliates as of December 31, 2014 and 2013 (in millions):
		December 31, 2014		December 31, 2013
	Accounts receivable	$	0.6	$	—
	Accounts payable	$	5.6	$	3.6

Segments_Tables

Segments (Tables)	12 Months Ended
	Dec. 31, 2014
Segment Reporting [Abstract]
Reportable Segments	Below is a reconciliation of our net income to EBITDA (in millions):
		Year Ended December 31,
		2014			2013			2012
	Net income (loss)	$	(10.4	)	$	(50.6	)	$	24.4
	Add:
	Interest and debt expense, net	127.1			77.9			35.8
	Provision for income taxes	1.1			1			1.2
	Depreciation, amortization and accretion	285.3			167.9			73.2
	EBITDA	$	403.1		$	196.2		$	134.6
	The following tables summarize the reportable segment data for the years ended December 31, 2014, 2013 and 2012 (in millions).
		Year Ended December 31, 2014
		Gathering and Processing			Storage and Transportation			NGL and Crude Services			Intersegment			Corporate			Total
	Revenues	$	332.5		$	192.9		$	3,406.90		$	(1.0	)	$	—		$	3,931.30
	Costs of product/services sold	71.3			24.8			3,070.20			(1.0		)	—			3,165.30
	Operations and maintenance expense	62.9			23.3			117.1			—			—			203.3
	General and administrative expense	—			—			—			—			100.2			100.2
	Gain (loss) on long-lived assets, net	(32.7		)	33.8			(3.0		)	—			—			(1.9		)
	Goodwill impairment	(18.5		)	—			(30.3		)	—			—			(48.8		)
	Loss on contingent consideration	(8.6		)	—			—			—			—			(8.6		)
	Earnings (loss) from unconsolidated affiliates	0.5			0.2			(1.4		)	—			—			(0.7		)
	Other income, net	—			—			—			—			0.6			0.6
	EBITDA	$	139		$	178.8		$	184.9		$	—		$	(99.6	)	$	403.1
	Goodwill	$	338.3		$	726.3		$	1,427.20		$	—		$	—		$	2,491.80
	Total assets	$	2,645.00		$	1,981.20		$	3,631.30		$	—		$	203.9		$	8,461.40
	Purchases of property, plant and equipment	$	245.7		$	9.7		$	160.4		$	—		$	8.2		$	424
		Year Ended December 31, 2013
		Gathering and Processing			Storage and Transportation			NGL and Crude Services			Intersegment			Corporate			Total
	Revenues	$	291.2		$	104.2		$	1,031.30		$	—		$	—		$	1,426.70
	Costs of product/services sold	56.6			15.7			930			—			—			1,002.30
	Operations and maintenance expense	54.9			12.1			37.6			—			—			104.6
	General and administrative expense	—			—			—			—			93.5			93.5
	Gain (loss) on long-lived assets	5.4			—			(0.1		)	—			—			5.3
	Goodwill impairment	(4.1		)	—			—			—			—			(4.1		)
	Loss on contingent consideration	(31.4		)	—			—			—			—			(31.4		)
	Earnings (loss) from unconsolidated affiliates	0.1			—			(0.2		)	—			—			(0.1		)
	Other income, net	—			—			—			—			0.2			0.2
	EBITDA	$	149.7		$	76.4		$	63.4		$	—		$	(93.3	)	$	196.2
	Goodwill	$	356.8		$	936.5		$	1,258.90		$	—		$	—		$	2,552.20
	Total assets	$	2,507.30		$	2,369.10		$	3,465.80		$	—		$	181		$	8,523.20
	Purchases of property, plant and equipment	$	271.2		$	18		$	56.8		$	—		$	1		$	347
		Year Ended December 31, 2012
		Gathering and Processing			Storage and Transportation			NGL and Crude Services			Intersegment			Corporate			Total
	Revenues	$	239.5		$	—		$	—		$	—		$	—		$	239.5
	Costs of product/services sold	39			—			—			—			—			39
	Operations and maintenance expense	43.1			—			—			—			—			43.1
	General and administrative expense	—			—			—			—			29.6			29.6
	Gain on contingent consideration	6.8			—			—			—			—			6.8
	EBITDA	$	164.2		$	—		$	—		$	—		$	(29.6	)	$	134.6
	Goodwill	$	352.2		$	—		$	—		$	—		$	—		$	352.2
	Total assets	$	2,278.90		$	—		$	—		$	—		$	22.7		$	2,301.60
	Purchases of property, plant and equipment	$	51.5		$	—		$	—		$	—		$	1.1		$	52.6

Condensed_Consolidating_Financ1

Condensed Consolidating Financial Information (Tables)	12 Months Ended
	Dec. 31, 2014
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
Schedule of Error Corrections and Prior Period Adjustments	As summarized in the table below, the condensed consolidating statement of cash flows for the year ended December 31, 2013 has been corrected for certain errors in presentation. There was no impact to our consolidated statement of cash flows for the year ended December 31, 2013.
		Parent						Guarantor Subsidiaries						Eliminations
		As Adjusted			As Previously Reported			As Adjusted			As Previously Reported			As Adjusted			As Previously Reported
		(in millions)
	Cash flows from operating activities:	$	(12.3	)	$	—		$	14.1		$	1.8		$	—		$	—
	Cash flows from investing activities:
	Capital contributions from consolidated affiliates, net and other	20.7			76			0.1			17			(20.7		)	(92.9		)
	Net cash provided by (used in) investing activities	20.7			76			(6.4		)	10.5			(20.7		)	(92.9		)
	Cash flows from financing activities:
	Proceeds from the issuance of long-term debt	394.1			—			—			394.1			—			—
	Principal payments on long-term debt	(333.3		)	—			—			(333.3		)	—			—
	Distributions paid to partners	(68.4		)	(76.0		)	—			(59.1		)	26.2			92.9
	Change in intercompany balances	0.4			—			(0.4		)	—			—			—
	Other	(1.1		)	0.1			(4.9		)	(11.6		)	(5.5		)	—
	Net cash provided by (used in) financing activities	(8.3		)	(75.9		)	(5.3		)	(9.9		)	20.7			92.9
Condensed Consolidating Balance Sheet
	Condensed Consolidating Balance Sheet
	31-Dec-14
	(in millions)
		Parent			Guarantor			Non-			Eliminations			Consolidated
					Subsidiaries			Guarantor
								Subsidiaries
	Assets
	Current assets:
	Cash	$	3.7		$	0.5		$	4.6		$	—		$	8.8
	Accounts receivable	—			137.5			241.5			—			379
	Accounts receivable - related party	—			0.3			0.3			—			0.6
	Accounts receivable - intercompany	3.2			—			—			(3.2		)	—
	Total accounts receivable	3.2			137.8			241.8			(3.2		)	379.6
	Inventories	—			38.6			8			—			46.6
	Other current assets	—			84.4			18.7			—			103.1
	Total current assets	6.9			261.3			273.1			(3.2		)	538.1
	Property, plant and equipment, net	2.5			227.1			3,664.20			—			3,893.80
	Goodwill and intangible assets, net	1.7			706.7			3,014.70			—			3,723.10
	Investment in consolidated affiliates	5,971.20			—			—			(5,971.2		)	—
	Investment in unconsolidated affiliates	—			—			295.1			—			295.1
	Other assets	—			9.9			1.4			—			11.3
	Total assets	$	5,982.30		$	1,205.00		$	7,248.50		$	(5,974.4	)	$	8,461.40
	Liabilities and partners' capital
	Current liabilities:
	Accounts payable	$	—		$	109.5		$	126.1		$	—		$	235.6
	Accounts payable - related party	—			2.5			3.1			—			5.6
	Accounts payable - intercompany	—			—			3.2			(3.2		)	—
	Total accounts payable	—			112			132.4			(3.2		)	241.2
	Other current liabilities	4.9			56.1			122.7			—			183.7
	Total current liabilities	4.9			168.1			255.1			(3.2		)	424.9
	Long-term liabilities:
	Long-term debt, less current portion	380			—			2,012.80			—			2,392.80
	Other long-term liabilities	12.9			15.1			31.2			—			59.2
	Total long-term liabilities	392.9			15.1			2,044.00			—			2,452.00
	Partners' capital	776.2			1,021.80			141.1			(1,162.9		)	776.2
	Interest of non-controlling partners in subsidiaries	4,808.30			—			4,808.30			(4,808.3		)	4,808.30
	Total partners' capital	5,584.50			1,021.80			4,949.40			(5,971.2		)	5,584.50
	Total liabilities and partners' capital	$	5,982.30		$	1,205.00		$	7,248.50		$	(5,974.4	)	$	8,461.40
	Condensed Consolidating Balance Sheet
	31-Dec-13
	(in millions)
		Parent			Guarantor			Non-			Eliminations			Consolidated
					Subsidiaries			Guarantor
								Subsidiaries
	Assets
	Current assets:
	Cash	$	0.1		$	2.4		$	2.7		$	—		$	5.2
	Accounts receivable	—			207.5			205.1			—			412.6
	Accounts receivable - intercompany	—			—			—			—			—
	Total accounts receivable	—			207.5			205.1			—			412.6
	Inventories	—			66.6			7			—			73.6
	Other current assets	—			25.8			10.2			(5.4		)	30.6
	Total current assets	0.1			302.3			225			(5.4		)	522
	Property, plant and equipment, net	—			400.9			3,504.40			—			3,905.30
	Goodwill and intangible assets, net	—			742.4			3,170.20			—			3,912.60
	Investment in consolidated affiliates	5,927.10			—			—			(5,927.1		)	—
	Investment in unconsolidated affiliates	—			—			151.4			—			151.4
	Other assets	—			10.2			21.7			—			31.9
	Total assets	$	5,927.20		$	1,455.80		$	7,072.70		$	(5,932.5	)	$	8,523.20
	Liabilities and partners' capital
	Current liabilities:
	Accounts payable	$	—		$	218.3		$	157.1		$	—		$	375.4
	Accounts payable - related party	—			—			3.6			—			3.6
Accounts payable - intercompany	—			—			—			—			—
Total accounts payable	—			218.3			160.7			—			379
Other current liabilities	4.2			61.6			156.7			(5.4		)	217.1
Total current liabilities	4.2			279.9			317.4			(5.4		)	596.1
Long-term liabilities:
Long-term debt, less current portion	393			—			1,867.90			—			2,260.90
Other long-term liabilities	21.4			109.9			26.3			—			157.6
Total long-term liabilities	414.4			109.9			1,894.20			—			2,418.50
Partners' capital	831.6			1,066.00			184.1			(1,250.1		)	831.6
Interest of non-controlling partners in subsidiaries	4,677.00			—			4,677.00			(4,677.0		)	4,677.00
Total partners' capital	5,508.60			1,066.00			4,861.10			(5,927.1		)	5,508.60
Total liabilities and partners' capital	$	5,927.20		$	1,455.80		$	7,072.70		$	(5,932.5	)	$	8,523.20
Condensed Consolidating Statements of Operations
	Condensed Consolidating Statements of Operations
	Year Ended December 31, 2014
	(in millions)
		Parent			Guarantor			Non-			Eliminations			Consolidated
					Subsidiaries			Guarantor
								Subsidiaries
	Revenues:
	Gathering and processing	$	—		$	—		$	328.5		$	—		$	328.5
	Storage and transportation	—			13.8			179.1			—			192.9
	NGL and crude services	—			1,366.60			2,040.30			—			3,406.90
	Related party	—			—			17.6			(14.6		)	3
		—			1,380.40			2,565.50			(14.6		)	3,931.30
	Costs of product/services sold:
	Gathering and processing	—			—			29.1			—			29.1
	Storage and transportation	—			10.5			14.3			—			24.8
	NGL and crude services	—			1,218.30			1,851.90			(1.0		)	3,069.20
	Related party	—			13.6			42.2			(13.6		)	42.2
		—			1,242.40			1,937.50			(14.6		)	3,165.30
	Expenses:
	Operations and maintenance	—			64.3			139			—			203.3
	General and administrative	8.5			6.3			85.4			—			100.2
	Depreciation, amortization and accretion	—			44.7			240.6			—			285.3
		8.5			115.3			465			—			588.8
	Other operating income (expense):
	Gain (loss) on long-lived assets, net	—			31.7			(33.6		)	—			(1.9		)
	Goodwill impairment	—			—			(48.8		)	—			(48.8		)
	Loss on contingent consideration	—			—			(8.6		)	—			(8.6		)
	Operating income (loss)	(8.5		)	54.4			72			—			117.9
	Earnings (loss) from unconsolidated affiliates, net	—			—			(0.7		)	—			(0.7		)
	Interest and debt expense, net	(15.7		)	—			(111.4		)	—			(127.1		)
	Other income, net	—			0.6			—			—			0.6
	Equity in net income (loss) of subsidiary	14.2			—			—			(14.2		)	—
	Income (loss) before income taxes	(10.0		)	55			(40.1		)	(14.2		)	(9.3		)
	Provision for income taxes	0.4			—			0.7			—			1.1
	Net income (loss)	(10.4		)	55			(40.8		)	(14.2		)	(10.4		)
	Net (income) loss attributable to non-controlling partners in subsidiaries	—			—			66.8			—			66.8
	Net income (loss) attributable to partners	$	(10.4	)	$	55		$	26		$	(14.2	)	$	56.4
	Condensed Consolidating Statements of Operations
	Year Ended December 31, 2013
	(in millions)
		Parent			Guarantor			Non-			Eliminations			Consolidated
					Subsidiaries			Guarantor
								Subsidiaries
	Revenues:
	Gathering and processing	$	—		$	—		$	216.3		$	—		$	216.3
	Storage and transportation	—			14.1			90.1			—			104.2
	NGL and crude services	—			761.2			270.1			—			1,031.30
	Related party	—			—			82.1			(7.2		)	74.9
		—			775.3			658.6			(7.2		)	1,426.70
	Costs of product/services sold:
	Gathering and processing	—			—			24.1			—			24.1
	Storage and transportation	—			7			8.7			—			15.7
	NGL and crude services	—			699.6			230.4			—			930
	Related party	—			7.2			32.5			(7.2		)	32.5
		—			713.8			295.7			(7.2		)	1,002.30
	Expenses:
	Operations and maintenance	—			31.3			73.3			—			104.6
	General and administrative	—			10			83.5			—			93.5
	Depreciation, amortization and accretion	—			26			141.9			—			167.9
		—			67.3			298.7			—			366
	Other operating income (expense):
	Gain (loss) on long-lived assets, net	—			(0.1		)	5.4			—			5.3
	Goodwill impairment	—			—			(4.1		)	—			(4.1		)
Loss on contingent consideration	—			—			(31.4		)	—			(31.4		)
Operating income (loss)	—			(5.9		)	34.1			—			28.2
Earnings (loss) from unconsolidated affiliates, net	—			—			(0.1		)	—			(0.1		)
Interest and debt expense, net	(6.5		)	—			(71.4		)	—			(77.9		)
Other income, net	—			0.2			—			—			0.2
Equity in net income (loss) of subsidiary	(43.9		)	—			—			43.9			—
Income (loss) before income taxes	(50.4		)	(5.7		)	(37.4		)	43.9			(49.6		)
Provision for income taxes	0.2			0.1			0.7			—			1
Net income (loss)	(50.6		)	(5.8		)	(38.1		)	43.9			(50.6		)
Net (income) loss attributable to non-controlling partners in subsidiaries	—			—			57.3			—			57.3
Net income (loss) attributable to partners	$	(50.6	)	$	(5.8	)	$	19.2		$	43.9		$	6.7
Condensed Consolidating Statements of Comprehensive Income
	Condensed Consolidating Statements of Comprehensive Income
	Year Ended December 31, 2014
	(in millions)
		Parent			Guarantor			Non-			Eliminations			Consolidated
					Subsidiaries			Guarantor
								Subsidiaries
	Net income (loss)	$	(10.4	)	$	55		$	(40.8	)	$	(14.2	)	$	(10.4	)
	Change in fair value of Suburban Propane Partners, LP units	(0.5		)	—			—			—			(0.5		)
	Comprehensive income (loss)	$	(10.9	)	$	55		$	(40.8	)	$	(14.2	)	$	(10.9	)
	Condensed Consolidating Statements of Comprehensive Income
	Year Ended December 31, 2013
	(in millions)
		Parent			Guarantor			Non-			Eliminations			Consolidated
					Subsidiaries			Guarantor
								Subsidiaries
	Net income (loss)	$	(50.6	)	$	(5.8	)	$	(38.1	)	$	43.9		$	(50.6	)
	Change in fair value of Suburban Propane Partners, LP units	(0.1		)	—			—			—			(0.1		)
	Comprehensive income (loss)	$	(50.7	)	$	(5.8	)	$	(38.1	)	$	43.9		$	(50.7	)
Condensed Consolidating Statements of Cash Flows
	Condensed Consolidating Statements of Cash Flows
	Year Ended December 31, 2014
	(in millions)
		Parent			Guarantor			Non-			Eliminations			Consolidated
					Subsidiaries			Guarantor
								Subsidiaries
	Cash flows from operating activities:	$	(25.3	)	$	(14.6	)	$	322.9		$	—		$	283
	Cash flows from investing activities:
	Acquisitions, net of cash acquired	—			—			(19.5		)	—			(19.5		)
	Purchases of property, plant and equipment	(3.8		)	(13.2		)	(407.0		)	—			(424.0		)
	Investment in unconsolidated affiliates	35.8			—			(144.4		)	—			(108.6		)
	Proceeds from the sale of assets	—			2.7			—			—			2.7
	Proceeds from the sale of Tres Palacios	66.4			—			—			—			66.4
	Capital contributions from consolidated affiliates, net	72.4			—			—			(72.4		)	—
	Net cash provided by (used in) investing activities	170.8			(10.5		)	(570.9		)	(72.4		)	(483.0		)
	Cash flows from financing activities:
	Proceeds from the issuance of long-term debt	734			—			2,089.90			—			2,823.90
	Principal payments on long-term debt	(746.2		)	—			(1,949.8		)	—			(2,696.0		)
	Payments on capital leases	—			—			(3.2		)	—			(3.2		)
	Payments for debt-related deferred costs	(1.8		)	—			(0.1		)	—			(1.9		)
	Distributions paid to partners	(102.5		)	—			(72.4		)	72.4			(102.5		)
	Distributions paid to non-controlling partners	—			—			(296.5		)	—			(296.5		)
	Net proceeds from issuance of preferred equity of subsidiary	—			—			53.9			—			53.9
	Net proceeds from issuance of CMLP Class A preferred units	—			—			430.5			—			430.5
	Taxes paid for unit-based compensation vesting	—			(2.3		)	(1.6		)	—			(3.9		)
	Change in intercompany balances	(25.4		)	25.4			—			—			—
	Other	—			0.1			(0.8		)	—			(0.7		)
	Net cash provided by (used in) financing activities	(141.9		)	23.2			249.9			72.4			203.6
	Net change in cash	3.6			(1.9		)	1.9			—			3.6
	Cash at beginning of period	0.1			2.4			2.7			—			5.2
	Cash at end of period	$	3.7		$	0.5		$	4.6		$	—		$	8.8
	Condensed Consolidating Statements of Cash Flows
	Year Ended December 31, 2013
	(in millions)
		Parent			Guarantor			Non-			Eliminations			Consolidated
					Subsidiaries			Guarantor
								Subsidiaries
	Cash flows from operating activities:	$	(12.3	)	$	14.1		$	186.5		$	—		$	188.3
	Cash flows from investing activities:
	Acquisitions, net of cash acquired	—			5.9			(561.5		)	—			(555.6		)
	Purchases of property, plant and equipment	—			(12.4		)	(334.6		)	—			(347.0		)
	Investment in unconsolidated affiliates, net	—			—			(151.5		)	—			(151.5		)
	Capital contributions from consolidated affiliates, net and other	20.7			0.1			11.1			(20.7		)	11.2
	Net cash provided by (used in) investing activities	20.7			(6.4		)	(1,036.5		)	(20.7		)	(1,042.9		)
	Cash flows from financing activities:
	Proceeds from the issuance of long-term debt	394.1			—			2,072.80			—			2,466.90
	Principal payments on long-term debt	(333.3		)	—			(1,634.3		)	—			(1,967.6		)
	Distributions paid to partners	(68.4		)	—			(155.2		)	26.2			(197.4		)
	Distributions paid to non-controlling partners	—			—			(204.5		)	—			(204.5		)
	Net proceeds from the issuance of CMLP common units	—			—			714			—			714
	Net proceeds from issuance of preferred equity of subsidiary	—			—			96.1			—			96.1
	Change in intercompany balances	0.4			(0.4		)	—			—			—
	Other	(1.1		)	(4.9		)	(36.3		)	(5.5		)	(47.8		)
	Net cash provided by (used in) financing activities	(8.3		)	(5.3		)	852.6			20.7			859.7
	Net increase in cash	0.1			2.4			2.6			—			5.1
	Cash at beginning of period	—			—			0.1			—			0.1
	Cash at end of period	$	0.1		$	2.4		$	2.7		$	—		$	5.2

Quarterly_Financial_Data_Unaud1

Quarterly Financial Data (Unaudited) (Tables)	12 Months Ended
	Dec. 31, 2014
Quarterly Financial Information Disclosure [Abstract]
Schedule of Quarterly Financial Information	Summarized unaudited quarterly financial data is presented below (in millions, except per unit information):
		Quarter Ended
		March 31				June 30			September 30			31-Dec
	2014
	Revenues	$	971.6			$	926.3		$	1,036.20		$	997.2
	Operating income (loss)	45.7				29.4			43			(0.2		)	(1)
	Earnings (loss) from unconsolidated affiliates, net	(0.1		)		(1.5		)	0.3			0.6
	Net income (loss)	13.2				(4.8		)	11.9			(30.7		)
	Net income (loss) attributable to partners	19.6				(4.4		)	2.8			38.4
	Net income (loss) per limited partner unit:
	Basic	$	0.11			$	(0.02	)	$	0.02		$	0.21
	Diluted	$	0.11			$	(0.02	)	$	0.02		$	0.21
	2013
	Revenues	$	72.4			$	118.9		$	427.2		$	808.2
	Operating income (loss)	15.7				7.8			15.8			(11.1		)	(2)
	Earnings (loss) from unconsolidated affiliates, net	—				—			(0.4		)	0.3
	Net income (loss)	3.9				(4.5		)	(7.9		)	(42.1		)
	Net income (loss) attributable to partners	5.1				1.6			(8.3		)	8.3
	Net income (loss) per limited partner unit:
	Basic(4)	$	0.13		(3)	$	0.03		$	(0.05	)	$	0.04
	Diluted(4)	$	0.13		(3)	$	0.03		$	(0.05	)	$	0.04
	-1	Includes goodwill, property, plant and equipment and intangible impairments of approximately $48.8 million, $13.2 million and $21.3 million, respectively. See Note 2 for a further discussion of our impairments recorded during 2014. In addition, include a gain of approximately $30.6 million on the sale of our interest in Tres Palacios. See Note 6, for a further discussion of our divestiture of Tres Palacios.
	-2	Includes a $31.4 million loss on contingent consideration which reflects the fair value of an earn-out premium associated with the original acquisition of our Antero assets. See Note 3 for a further discussion of this non-cash charge.
	-3	Basic and diluted net income for the quarter ended March 31, 2013, were calculated based on the presumption that the common and subordinated units issued to acquire Legacy Crestwood GP (the accounting predecessor) were outstanding for the entire period prior to the June 19, 2013 acquisition.
	-4	The accumulation of basic and diluted net income (loss) per limited partner unit does not total the amount for the year due to changes in ownership percentages throughout the year.

Organization_and_Description_o1

Organization and Description of Business (Narrative) (Detail) (USD $)	0 Months Ended	12 Months Ended		0 Months Ended
In Millions, except Share data, unless otherwise specified	Jun. 19, 2013	Dec. 31, 2014	Dec. 31, 2013	Oct. 07, 2013	6-May-13	Jun. 05, 2013
		segment
Partnership Organization And Basis Of Presentation [Line Items]
General partner ownership percentage	100.00%
Distribution made to limited partners		387,991	633,084
Number of operating segments		3
CMLP
Partnership Organization And Basis Of Presentation [Line Items]
Cash				$34.90
Cash payments to unitholders upon completion of merger, per unit				1.03
CMLP
Partnership Organization And Basis Of Presentation [Line Items]
Distribution percentage		50.00%
Crestwood Equity Partners LP
Partnership Organization And Basis Of Presentation [Line Items]
General partner ownership percentage		4.00%
Inergy Midstream
Partnership Organization And Basis Of Presentation [Line Items]
Cash payments to unitholders upon completion of merger					24.9
Crestwood Holdings
Partnership Organization And Basis Of Presentation [Line Items]
Cash payments to unitholders upon completion of merger					$10
CMLP
Partnership Organization And Basis Of Presentation [Line Items]
Conversion ratio				1.07
Distribution Rights
Partnership Organization And Basis Of Presentation [Line Items]
Distribution declared per limited partner unit		0.37
Distribution Rights | Crestwood Equity Partners LP
Partnership Organization And Basis Of Presentation [Line Items]
Distribution percentage		100.00%
Majority Shareholder | Affiliated Entity | Unit Distribution
Partnership Organization And Basis Of Presentation [Line Items]
Distribution made to limited partners	56,400,000
Crestwood Holdings | Crestwood Equity Partners LP
Partnership Organization And Basis Of Presentation [Line Items]
Shares issued by acquiree				14,300,000
Crestwood Holdings | Majority Shareholder
Partnership Organization And Basis Of Presentation [Line Items]
Shares exchanged by acquirer				7,100,000
Class D Units | Majority Shareholder | Affiliated Entity | Unit Distribution
Partnership Organization And Basis Of Presentation [Line Items]
Distribution made to limited partners						21,588
Common Units | Majority Shareholder | Affiliated Entity | Unit Distribution
Partnership Organization And Basis Of Presentation [Line Items]
Distribution made to limited partners						137,105
Common Unit Capital | First Reserve Management, L.P.
Partnership Organization And Basis Of Presentation [Line Items]
General partner ownership percentage		27.00%
Common Unit Capital | CMLP
Partnership Organization And Basis Of Presentation [Line Items]
General partner ownership percentage		11.00%
Subordinated Unit
Partnership Organization And Basis Of Presentation [Line Items]
Units of partnership interest, amount		4,387,889

Basis_of_Presentation_and_Summ3

Basis of Presentation and Summary of Significant Accounting Policies (Narrative) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jun. 19, 2013
	reporting_units
Summary Of Significant Accounting Policies [Line Items]
Impaired assets to be disposed of	$13.20
Impairment of intangible assets	21.3
Property, plant and equipment	4,273.90	4,108.70
Deferred revenue	12.2	2.1
Goodwill impairment	48.8	4.1	0
Number of Reporting Units with Goodwill Impairment Loss	4
Number of Reporting Units	14
Goodwill	2,491.80	2,552.20	352.2	2,134.80
Percentage of gross income from qualifying sources required to be subject to federal income tax, minimum	90.00%
Discount rate	9.00%
Granite Wash
Summary Of Significant Accounting Policies [Line Items]
Property, plant and equipment	20.2
Goodwill impairment	14.2
Watkins Glen
Summary Of Significant Accounting Policies [Line Items]
Goodwill impairment	28.1
Goodwill	66.2
US Salt
Summary Of Significant Accounting Policies [Line Items]
Goodwill impairment	2.2
Goodwill	12.6
Fayetteville
Summary Of Significant Accounting Policies [Line Items]
Goodwill impairment	4.3
Goodwill	$72.50

Basis_of_Presentation_and_Summ4

Basis of Presentation and Summary of Significant Accounting Policies (Estimated Useful Lives Of Property, Plant And Equipment) (Detail)	12 Months Ended
	Dec. 31, 2014
Gathering systems and pipelines | Minimum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	20 years
Gathering systems and pipelines | Maximum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	20 years
Facilities and equipment | Minimum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	20 years
Facilities and equipment | Maximum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	25 years
Buildings, land, rights-of-way, storage contracts and easements | Minimum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	20 years
Buildings, land, rights-of-way, storage contracts and easements | Maximum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	40 years
Office furniture and fixtures | Minimum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	5 years
Office furniture and fixtures | Maximum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	10 years
Vehicles | Minimum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	5 years
Vehicles | Maximum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	5 years

Basis_of_Presentation_and_Summ5

Basis of Presentation and Summary of Significant Accounting Policies (Estimated Economic Lives Of Intangible Assets) (Detail)	12 Months Ended
	Dec. 31, 2014
Customer Relationships
Finite-Lived Intangible Assets [Line Items]
Weighted-Average Life (years)	22 years
Covenants not to compete
Finite-Lived Intangible Assets [Line Items]
Weighted-Average Life (years)	5 years
Trademarks
Finite-Lived Intangible Assets [Line Items]
Weighted-Average Life (years)	6 years

Acquisitions_Narrative_Details

Acquisitions (Narrative) (Details) (USD $)	0 Months Ended	12 Months Ended			0 Months Ended		6 Months Ended		0 Months Ended	1 Months Ended	0 Months Ended	3 Months Ended		0 Months Ended
	Jan. 08, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Mar. 21, 2014	9-May-14	Jun. 30, 2014	Dec. 31, 2013	Nov. 08, 2013	Oct. 31, 2013	Mar. 26, 2012	Dec. 31, 2014	Mar. 31, 2013	Aug. 24, 2013	Aug. 24, 2012	Dec. 28, 2013	Dec. 28, 2012	Jun. 19, 2013	Sep. 14, 2012	Feb. 29, 2012	Oct. 08, 2013	Feb. 28, 2015	Dec. 31, 2018
																					acre		ft3
Business Acquisition [Line Items]
Consideration transferred	$258,000,000
Property, plant and equipment																		2,088,100,000
Goodwill		2,491,800,000	2,552,200,000	352,200,000				2,552,200,000				2,491,800,000						2,134,800,000
(Gain) loss on contingent consideration		8,600,000	31,400,000	-6,800,000
Discount rate		9.00%
Percentage of voting interests acquired																			99.00%	65.00%
Crude Oil and NGL
Business Acquisition [Line Items]
Goodwill		1,427,200,000	1,258,900,000	0				1,258,900,000				1,427,200,000
Storage and Transportation
Business Acquisition [Line Items]
Goodwill		726,300,000	936,500,000	0				936,500,000				726,300,000
Red Rock Transportation, Inc.
Business Acquisition [Line Items]
Consideration transferred					13,800,000
Cash					12,100,000
Liabilities incurred					1,800,000
Number of trailer tanks					56
Number of Double Bottom tanks					22
Number of Tractors					44
Crude hauling capacity, per day					28,000
Property, plant and equipment					10,600,000
Goodwill					3,200,000
LT Enterprises
Business Acquisition [Line Items]
Consideration transferred						10,700,000
Cash						9,000,000
Liabilities incurred						1,700,000
Number of Tractors						38
Crude hauling capacity, per day						20,000
Number of Crude Trailers						51
Number of Service Vehicles						17
Land (in acres)						20
Inergy Midstream
Business Acquisition [Line Items]
Reduction in preliminary estimate							15,300,000
Operating income of acquiree since acquisition date								23,900,000
Transaction costs		3,400,000	30,100,000					30,100,000				3,400,000
Revenue of acquiree since acquisition date								916,700,000
Inergy Midstream | Crude Oil and NGL
Business Acquisition [Line Items]
Goodwill																		1,408,500,000
Arrow Midstream Holdings, LLC
Business Acquisition [Line Items]
Consideration transferred									750,000,000
Cash										550,000,000
Property, plant and equipment									400,500,000
Goodwill									45,900,000
Operating income of acquiree since acquisition date			1,700,000
Transaction costs		5,400,000	1,200,000					1,200,000				5,400,000
Revenue of acquiree since acquisition date			218,800,000
Other consideration transferred									11,300,000
Common units in acquisition										8,826,125
Central delivery point acquired (in acres)																					23
Antero
Business Acquisition [Line Items]
Consideration transferred											376,800,000
Gathering pipeline acquired (in miles)											33
Contingent consideration, liability											40,000,000
(Gain) loss on contingent consideration												-40,000,000	-31,400,000
Discount rate			5.90%
Long-term purchase commitment		20 years
Gross acres acquired											127,000
Purchase agreement, assets acquired, net (in acres)											104,000
Deferred revenue				2,600,000
Accounts payable, other			2,400,000					2,400,000
Antero | Subsequent Event
Business Acquisition [Line Items]
Contingent consideration, current liability																						40,000,000
Antero | Minimum
Business Acquisition [Line Items]
Volume of of natural gas acquired, per day											300,000,000
Antero | Minimum | Scenario, Forecast
Business Acquisition [Line Items]
Volume of of natural gas acquired, per day																							450,000,000
Devon
Business Acquisition [Line Items]
Consideration transferred															87,300,000
Cash														87,900,000
Property, plant and equipment														88,600,000
Long-term purchase commitment		20 years
Depreciation			-2,200,000
EMAC
Business Acquisition [Line Items]
Consideration transferred																	95,000,000
Cash																95,000,000
Property, plant and equipment																53,400,000
Goodwill																8,600,000
Depreciation			($700,000)

Acquisitions_Assets_Acquired_L

Acquisitions (Assets Acquired, Liabilities Assumed) (Details) (USD $)	12 Months Ended			1 Months Ended	0 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Oct. 31, 2013	Aug. 24, 2013	Dec. 28, 2013	Jun. 19, 2013	Nov. 08, 2013
Change in Accounting Estimate [Line Items]
Current assets							$224.50
Property, plant and equipment							2,088.10
Intangible assets							337.5
Other assets							12.7
Total identifiable assets acquired							2,662.80
Current liabilities							207.6
Assets retirement obligations	23.8	15.1	14
Long-term debt							1,079.30
Other long-term liabilities							146.6
Total liabilities assumed							1,433.50
Net identifiable assets acquired							1,229.30
Goodwill	2,491.80	2,552.20	352.2				2,134.80
Net assets acquired							3,364.10
Total purchase price	19.5	555.6	564
Arrow Midstream Holdings, LLC
Change in Accounting Estimate [Line Items]
Current assets								192.7
Property, plant and equipment								400.5
Intangible assets								323.4
Other assets								19.5
Total identifiable assets acquired								936.1
Current liabilities								215.8
Assets retirement obligations								1.2
Other long-term liabilities								3.7
Total liabilities assumed								220.7
Net identifiable assets acquired								715.4
Goodwill								45.9
Net assets acquired								761.3
Cash				550
Devon
Change in Accounting Estimate [Line Items]
Property, plant and equipment					88.6
Total identifiable assets acquired					88.6
Total liabilities assumed					0.7
Cash					87.9
Total purchase price					87.9
Asset retirement obligation					0.5
Environmental liability					0.2
EMAC
Change in Accounting Estimate [Line Items]
Property, plant and equipment						53.4
Intangible assets						33.9
Total identifiable assets acquired						95.9
Total liabilities assumed						0.9
Goodwill						8.6
Cash						95
Total purchase price						95
Asset retirement obligation						0.8
Environmental liability						$0.10

Acquisitions_Pro_Forma_Revenue

Acquisitions (Pro Forma Revenues) (Details) (Rangeland Energy, LLC, USD $)	12 Months Ended
In Millions, except Per Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Rangeland Energy, LLC
Business Acquisition [Line Items]
Revenues	$3,449.30	$2,267.20
Net income	$3.90	$49.80
Net income per limited partner unit: Basic (usd per unit)	$0.04	$0.31
Net income per limited partner unit: Basic (usd per unit)	$0.04	$0.29

Certain_Balance_Sheet_Informat2

Certain Balance Sheet Information (Inventories) (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Balance Sheet Related Disclosures [Abstract]
NGLs	$37.50	$66.90
Parts, supplies and other	9.1	6.7
Total inventory	$46.60	$73.60

Certain_Balance_Sheet_Informat3

Certain Balance Sheet Information (Property, Plant And Equipment) (Details) (USD $)	1 Months Ended	12 Months Ended
In Millions, unless otherwise specified	Jul. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Property, Plant and Equipment [Line Items]
Property, plant and equipment		$4,273.90	$4,108.70
Less: accumulated depreciation and depletion		380.1	203.4
Property, plant and equipment, net		3,893.80	3,905.30
Depreciation		184.2	109.9	49.1
Depletion		0.7	0.4
Interest Costs Capitalized		7.7	3.4
Capital Leased Assets, Gross		5.3	5
Proceeds from sale of long lived assets	11	66.4	0	0
Gathering systems and pipelines
Property, Plant and Equipment [Line Items]
Property, plant and equipment		1,410.90	1,473.40
Facilities and equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment		1,648.30	1,186.50
Gain (loss) on long-lived assets, net			4.4
Buildings, land, rights-of-way, storage contracts and easements
Property, Plant and Equipment [Line Items]
Property, plant and equipment		841.5	814.7
Vehicles
Property, Plant and Equipment [Line Items]
Property, plant and equipment		45.2	35.8
Construction in process
Property, Plant and Equipment [Line Items]
Property, plant and equipment		156.5	365.8
Base gas
Property, Plant and Equipment [Line Items]
Property, plant and equipment		37.5	102
Salt deposits
Property, Plant and Equipment [Line Items]
Property, plant and equipment		120.5	120.5
Office furniture and fixtures
Property, Plant and Equipment [Line Items]
Property, plant and equipment		$13.50	$10

Certain_Balance_Sheet_Informat4

Certain Balance Sheet Information (Intangible Assets) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross	$1,441.90	$1,466.40
Less: accumulated amortization	210.6	106
Total intangible assets, net	1,231.30	1,360.40
Amortization of Intangible Assets and Interest Expense	109.8	66.7	28.9
Customer accounts
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross	583.7	576.9
Less: accumulated amortization	72.5	18.7
Covenants not to compete
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross	9.6	7
Less: accumulated amortization	3.2	1
Gathering systems and pipelines
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross	730.2	750.2
Less: accumulated amortization	98	67.3
Acquired storage contracts
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross	29	43.5
Less: accumulated amortization	12.7	8.6
Trademarks
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross	32.2	33.5
Less: accumulated amortization	6.7	2.3
Deferred financing and other costs
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross	57.2	55.3
Less: accumulated amortization	$17.50	$8.10

Certain_Balance_Sheet_Informat5

Certain Balance Sheet Information (Amortization and Interest Expense, Fiscal Year Maturity) (Details) (USD $)	Dec. 31, 2014
In Millions, unless otherwise specified
Goodwill and Intangible Assets Disclosure [Abstract]
2015	$115.10
2016	101.2
2017	87.5
2018	73.9
2019	$65.50

Certain_Balance_Sheet_Informat6

Certain Balance Sheet Information (Accrued Expenses and Other Liabilities) (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Payables and Accruals [Abstract]
Accrued expenses	$52.50	$40.30
Accrued property taxes	2.2	9.4
Accrued product purchases payable	0.7	1.6
Tax payable	1.6	14.8
Interest payable	23.5	16.7
Accrued additions to property, plant and equipment	20	58.2
Commitments and contingent liabilities (Note 15)	40	31.4
Capital leases	1.9	2.6
Deferred revenue	12.2	2.1
Total accrued expenses and other liabilities	$154.60	$177.10

Asset_Retirement_Obligations_D

Asset Retirement Obligations (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Net asset retirement obligation at January 1	$15.10	$14
Liabilities incurred	4.6	0
Acquisitions	1.2	0
Accretion expense	-1.1	-0.8
Changes in estimate	1.8	0.3
Net asset retirement obligation at December 31	$23.80	$15.10

Investments_in_Unconsolidated_1

Investments in Unconsolidated Affiliates (Details) (USD $)	0 Months Ended	1 Months Ended	3 Months Ended								12 Months Ended			1 Months Ended			0 Months Ended		4 Months Ended
	Jan. 08, 2013	Feb. 29, 2012	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2014	Feb. 28, 2015	Jul. 31, 2013	Jul. 19, 2013	Sep. 04, 2013	Dec. 31, 2013	Sep. 14, 2012
														mi
														in
														systems
Schedule of Equity Method Investments [Line Items]
Percentage of voting interests acquired		65.00%																		99.00%
Consideration transferred	$258,000,000
Investment in unconsolidated affiliates in period		131,300,000									108,600,000	151,500,000	0
Investment in unconsolidated affiliates (Note 6)			295,100,000				151,400,000				295,100,000	151,400,000		295,100,000					151,400,000
Earnings (loss) from unconsolidated affiliates, net			600,000	300,000	-1,500,000	-100,000	300,000	-400,000	0	0	-700,000	-100,000	0
Equity method ownership percentage		35.00%
Jackalope Gas Gathering Services, LLC
Schedule of Equity Method Investments [Line Items]
Investment in unconsolidated affiliates (Note 6)			232,900,000				127,200,000				232,900,000	127,200,000		232,900,000					127,200,000
Tres Palacios Holdings LLC
Schedule of Equity Method Investments [Line Items]
Investment in unconsolidated affiliates in period														132,800,000
Investment in unconsolidated affiliates (Note 6)			36,000,000								36,000,000			36,000,000
Earnings (loss) from unconsolidated affiliates, net											100,000
Difference between carrying amount and underlying equity			30,600,000								30,600,000			30,600,000
Amortization											100,000
Equity method ownership percentage			50.01%								50.01%			50.01%
Significant Acquisitions and Disposals, Gain (Loss) on Sale or Disposal, Net of Tax			30,600,000								30,600,000			30,600,000
Miles of pipeline			60								60			60
Diameter of pipeline			24								24			24
Number of pipeline systems			10								10			10
Powder River Basin Industrial Complex, LLC
Schedule of Equity Method Investments [Line Items]
Investment in unconsolidated affiliates (Note 6)			26,200,000				24,200,000				26,200,000	24,200,000		26,200,000					24,200,000
Equity method ownership percentage																		50.00%
Powder River Basin Industrial Complex, LLC | Subsequent Event
Schedule of Equity Method Investments [Line Items]
Proceeds from Equity Method Investment, Dividends or Distributions, Return of Capital															300,000
Powder River Basin Industrial Complex, LLC | Majority Shareholder
Schedule of Equity Method Investments [Line Items]
Earnings (loss) from unconsolidated affiliates, net											-1,400,000	-200,000
RKI Exploration and Production, LLC's | Jackalope Gas Gathering Services, LLC
Schedule of Equity Method Investments [Line Items]
Earnings (loss) from unconsolidated affiliates, net											3,600,000	1,500,000
Difference between carrying amount and underlying equity			53,700,000								53,700,000			53,700,000
Amortization											-3,100,000	-1,400,000
Crestwood Niobrara LLC | Jackalope Gas Gathering Services, LLC
Schedule of Equity Method Investments [Line Items]
Investment in unconsolidated affiliates in period										19,600,000	105,200,000
Crestwood Niobrara LLC | RKI Exploration and Production, LLC's
Schedule of Equity Method Investments [Line Items]
Consideration transferred																107,500,000
Access Midstream Partners, L.P. | RKI Exploration and Production, LLC's
Schedule of Equity Method Investments [Line Items]
Percentage of voting interests acquired																	50.00%
Long-term purchase commitment																	20 years
Crestwood Equity Partners LP | Tres Palacios Storage Company LLC
Schedule of Equity Method Investments [Line Items]
Equity method ownership percentage			100.00%								100.00%			100.00%
Crestwood Equity Partners LP | Tres Palacios Holdings LLC
Schedule of Equity Method Investments [Line Items]
Investment in unconsolidated affiliates (Note 6)			35,800,000								35,800,000			35,800,000
Tres Palacios Storage Company LLC
Schedule of Equity Method Investments [Line Items]
Storage capacity			38,400,000,000								38,400,000,000			38,400,000,000
CMLP | Tres Palacios Holdings LLC
Schedule of Equity Method Investments [Line Items]
Investment in unconsolidated affiliates in period														66,400,000
Equity method ownership percentage			50.01%								50.01%			50.01%
Brookfield Infrastructure Group | Tres Palacios Holdings LLC
Schedule of Equity Method Investments [Line Items]
Equity method ownership percentage			49.99%								49.99%			49.99%
Crude Logistics LLC | Powder River Basin Industrial Complex, LLC
Schedule of Equity Method Investments [Line Items]
Investment in unconsolidated affiliates in period											$3,400,000							$22,500,000	$1,900,000
Tres Palacios South Pipeline Lateral | Tres Palacios Holdings LLC
Schedule of Equity Method Investments [Line Items]
Miles of pipeline			11								11			11
Tres Palacios North Pipeline Lateral | Tres Palacios Holdings LLC
Schedule of Equity Method Investments [Line Items]
Miles of pipeline			51								51			51

Risk_Management_Notional_Amoun

Risk Management (Notional Amounts and Terms of Company's Derivative Financial Instruments) (Details)	Dec. 31, 2014	Dec. 31, 2013
	bbl	bbl
Propane, crude and heating oil (barrels) | Fixed Price Payor
Derivative [Line Items]
Propane, crude and heating oil (barrels)	6,800,000	5,600,000
Propane, crude and heating oil (barrels) | Fixed Price Receiver
Derivative [Line Items]
Propane, crude and heating oil (barrels)	8,400,000	6,800,000
Natural gas (MMBTU’s) | Fixed Price Payor
Derivative [Line Items]
Propane, crude and heating oil (barrels)	200,000	0
Natural gas (MMBTU’s) | Fixed Price Receiver
Derivative [Line Items]
Propane, crude and heating oil (barrels)	100,000	0

Risk_Management_Narrative_Deta

Risk Management (Narrative) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Derivative [Line Items]
Collateral posted for commodity derivative instruments	$33.60	$5.90
Commodity contract
Derivative [Line Items]
Aggregate fair value of commodity derivative instruments	5.2	16.6
Collateral posted for commodity derivative instruments	1.8	2.6
NYMEX margin deposit
Derivative [Line Items]
NYMEX margin deposit	5	3.6
Price Risk Contracts | Maximum
Derivative [Line Items]
Remaining maturity	35 months
Percent of contracts expiring in next twelve months	95.00%
Products and services sold
Derivative [Line Items]
Gain (Loss) on derivative instruments not designated as hedging	$51.20	($11.20)

Fair_Value_Measurements_Schedu

Fair Value Measurements (Schedule of Carrying Values and Estimated Fair Values of Senior Notes) (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Carrying Amount	$500,000,000
Fair Value	11,600,000	11,600,000
CEQP Senior Notes
Debt Instrument [Line Items]
Carrying Amount	11,400,000	11,400,000
CMLP
Debt Instrument [Line Items]
Carrying Amount		500,000,000
CMLP | Crestwood Midstream 2019 Senior Notes
Debt Instrument [Line Items]
Carrying Amount	351,000,000	351,200,000
Fair Value	360,500,000	379,300,000
CMLP | Crestwood Midstream 2020 Senior Notes
Debt Instrument [Line Items]
Carrying Amount	504,000,000	504,700,000
Fair Value	481,600,000	513,800,000
CMLP | Crestwood Midstream 2022 senior unsecured notes
Debt Instrument [Line Items]
Carrying Amount		600,000,000
Fair Value	568,500,000	617,300,000
Senior Notes, 2022 | CMLP | Crestwood Midstream 2022 senior unsecured notes
Debt Instrument [Line Items]
Carrying Amount	$600,000,000

Fair_Value_Measurements_Assets

Fair Value Measurements (Assets And Liabilities Measured At Fair Value On Recurring Basis) (Details) (Fair Value, Measurements, Recurring, USD $)	Dec. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Assets, Fair Value Disclosure [Abstract]
Assets from price risk management	$147.20	$28
Assets from price risk management, Total	79.8	14.5
SPH units	6.1	6.7
Assets, Fair Value Disclosure, Excluding Netting Adjustments	153.3	34.7
Netting Agreements	-67.4	-13.5
Total assets at fair value	85.9	21.2
Liabilities, Fair Value Disclosure [Abstract]
Liabilities from price risk management	100.8	39.6
Liabilities from price risk management, Total	25.4	34.9
Interest rate swaps	1.6	4.3
Liabilities, Fair Value Disclosure, Excluding Netting Adjustments	102.4	43.9
Netting Agreements	-75.4	-4.7
Total liabilities at fair value	27	39.2
Level 1
Assets, Fair Value Disclosure [Abstract]
Assets from price risk management	0.5	0.3
SPH units	6.1	6.7
Assets, Fair Value Disclosure, Excluding Netting Adjustments	6.6	7
Liabilities, Fair Value Disclosure [Abstract]
Liabilities from price risk management	1.6	0.1
Interest rate swaps	0	0
Liabilities, Fair Value Disclosure, Excluding Netting Adjustments	1.6	0.1
Level 2
Assets, Fair Value Disclosure [Abstract]
Assets from price risk management	146.7	27.7
SPH units	0	0
Assets, Fair Value Disclosure, Excluding Netting Adjustments	146.7	27.7
Liabilities, Fair Value Disclosure [Abstract]
Liabilities from price risk management	99.2	39.5
Interest rate swaps	1.6	4.3
Liabilities, Fair Value Disclosure, Excluding Netting Adjustments	100.8	43.8
Level 3
Assets, Fair Value Disclosure [Abstract]
Assets from price risk management	0	0
SPH units	0	0
Assets, Fair Value Disclosure, Excluding Netting Adjustments	0	0
Liabilities, Fair Value Disclosure [Abstract]
Liabilities from price risk management	0	0
Interest rate swaps	0	0
Liabilities, Fair Value Disclosure, Excluding Netting Adjustments	$0	$0

LongTerm_Debt_Components_Of_Lo

Long-Term Debt (Components Of Long-Term Debt) (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Carrying Amount	$500,000,000
Obligations under noncompetition agreements and notes to former owners of businesses acquired	6,100,000	2,800,000
Total debt	2,396,500,000	2,266,000,000
Less: current portion	3,700,000	5,100,000
Total long-term debt	2,392,800,000	2,260,900,000
Revolving Loan Facility
Debt Instrument [Line Items]
Credit agreement outstanding carrying value	369,000,000	381,000,000
CEQP Senior Notes
Debt Instrument [Line Items]
Carrying Amount	11,400,000	11,400,000
CMLP
Debt Instrument [Line Items]
Carrying Amount	350,000,000	350,000,000
Premium on senior notes	1,000,000	1,200,000
Crestwood Midstream 2020 Senior Notes
Debt Instrument [Line Items]
Fair value adjustment	4,000,000	4,700,000
Crestwood Midstream Revolver | Revolving Credit Facility
Debt Instrument [Line Items]
Credit agreement outstanding carrying value	555,000,000	414,900,000
CMLP
Debt Instrument [Line Items]
Carrying Amount		500,000,000
CMLP | Crestwood Midstream 2020 Senior Notes
Debt Instrument [Line Items]
Carrying Amount	504,000,000	504,700,000
CMLP | Crestwood Midstream 2019 Senior Notes
Debt Instrument [Line Items]
Carrying Amount	351,000,000	351,200,000
CMLP | Crestwood Midstream 2022 senior unsecured notes
Debt Instrument [Line Items]
Carrying Amount		600,000,000
CMLP | Senior Notes, 2022 | Crestwood Midstream 2022 senior unsecured notes
Debt Instrument [Line Items]
Carrying Amount	$600,000,000

LongTerm_Debt_Narrative_Detail

Long-Term Debt (Narrative) (Detail) (USD $)	1 Months Ended	12 Months Ended	0 Months Ended	3 Months Ended
	Dec. 31, 2014	Dec. 31, 2014	Oct. 07, 2013	Sep. 30, 2014	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 07, 2012	Feb. 29, 2012	Dec. 31, 2013	Nov. 08, 2012	Apr. 02, 2011	Oct. 22, 2013	Apr. 30, 2011	Dec. 03, 2014	Sep. 10, 2014	Sep. 09, 2014
Debt Instrument [Line Items]
Unapplied cash from asset disposition threshold	$50,000,000	$50,000,000
Debt issuance costs	500,000
Carrying amount	500,000,000	500,000,000
Interest rate, stated percentage	7.00%	7.00%						6.00%
Equity method ownership percentage									35.00%
Financial Guarantee
Debt Instrument [Line Items]
Interest rate, stated percentage	7.50%	7.50%
Guarantor obligations, maximum exposure, undisounted	497,000,000	497,000,000
CMLP
Debt Instrument [Line Items]
Carrying amount										500,000,000
Credit Agreement
Debt Instrument [Line Items]
Letters of credit outstanding	56,700,000	56,700,000								52,700,000
Credit Agreement amount available	69,300,000	69,300,000
Consolidated EBITDA to consolidated interest expense		8.32
Senior secured funded debt to consolidated EBITDA as defined in credit agreement		3.87
Interest Rate Swap, Maturing 2016
Debt Instrument [Line Items]
Number of interest rate derivatives held	6	6
Fixed rate, range low end	0.84%	0.84%
Fixed rate, range high end	2.52%	2.52%
Aggregate notional amount, cash flow hedges	225,000,000	225,000,000
Interest income (expense), net		2,600,000
Minimum | Credit Agreement
Debt Instrument [Line Items]
Consolidated EBITDA to consolidated interest expense		2.5
Revolving Loan Facility
Debt Instrument [Line Items]
Total funded debt to consolidated EBITDA		4.75
Revolving Loan Facility | Minimum | London Interbank Offered Rate
Debt Instrument [Line Items]
Interest rate at the end of the period	2.91%	2.91%								2.67%
Revolving Loan Facility | Maximum | London Interbank Offered Rate
Debt Instrument [Line Items]
Interest rate at the end of the period	5.00%	5.00%								4.75%
Crestwood Midstream 2020 Senior Notes
Debt Instrument [Line Items]
Letters of credit outstanding	15,100,000	15,100,000								30,700,000
Unused borrowing capacity	429,900,000	429,900,000
CMLP
Debt Instrument [Line Items]
Carrying amount	350,000,000	350,000,000								350,000,000
Crestwood Midstream 2019 Senior Notes | CMLP
Debt Instrument [Line Items]
Carrying amount	351,000,000	351,000,000								351,200,000
Crestwood Midstream 2019 Senior Notes | CMLP Senior Notes
Debt Instrument [Line Items]
Carrying amount											150,000,000	200,000,000
Revolving Loan Facility
Debt Instrument [Line Items]
Credit agreement outstanding carrying value	369,000,000	369,000,000								381,000,000
Revolving Loan Facility | CMLP
Debt Instrument [Line Items]
Credit agreement outstanding carrying value			1,000,000,000
Expiration period			5 years
Crestwood Midstream 2020 Senior Notes
Debt Instrument [Line Items]
Fair value adjustment	4,000,000	4,000,000								4,700,000
Crestwood Midstream 2020 Senior Notes | CMLP
Debt Instrument [Line Items]
Carrying amount	504,000,000	504,000,000								504,700,000
Crestwood Midstream 2022 senior unsecured notes | CMLP
Debt Instrument [Line Items]
Carrying amount										600,000,000
Senior Notes, 2022 | Crestwood Midstream 2019 Senior Notes
Debt Instrument [Line Items]
Interest rate, stated percentage													6.13%
Face amount													600,000,000
Senior Notes, 2022 | Crestwood Midstream 2022 senior unsecured notes | CMLP
Debt Instrument [Line Items]
Carrying amount	600,000,000	600,000,000
Crestwood Midstream Revolver
Debt Instrument [Line Items]
Total funded debt to consolidated EBITDA		4.5
Consolidated EBITDA to consolidated interest expense		3.99
Crestwood Midstream Revolver | Line of Credit, Excluding Bridge Loans | Minimum
Debt Instrument [Line Items]
Contingent margin	0.75%	0.75%
Crestwood Midstream Revolver | Line of Credit, Excluding Bridge Loans | Maximum
Debt Instrument [Line Items]
Contingent margin	1.75%	1.75%
Crestwood Midstream Revolver | Revolving Credit Facility
Debt Instrument [Line Items]
Credit agreement outstanding carrying value	555,000,000	555,000,000								414,900,000
Weighted average interest rate	2.86%	2.86%								2.75%
Consolidated leverage ratio, maximum		5
Consolidated leverage ratio, maximum, post acquisition		5.5
Interest coverage ratio, minimum		2.5
Crestwood Midstream Revolver | Revolving Credit Facility | Minimum
Debt Instrument [Line Items]
Weighted average interest rate	2.66%	2.66%								2.67%
Commitment fee percentage		0.30%
Crestwood Midstream Revolver | Revolving Credit Facility | Maximum
Debt Instrument [Line Items]
Weighted average interest rate	4.75%	4.75%								4.75%
Commitment fee percentage		0.50%
Crestwood Midstream Revolver | Swing Line Loans
Debt Instrument [Line Items]
Credit agreement outstanding carrying value			25,000,000
Crestwood Midstream Revolver | Standby Letters of Credit
Debt Instrument [Line Items]
Credit agreement outstanding carrying value			250,000,000
Senior Notes, 2019 | Crestwood Midstream 2019 Senior Notes
Debt Instrument [Line Items]
Interest rate, stated percentage														7.75%
Senior Notes, 2020 | Crestwood Midstream 2019 Senior Notes
Debt Instrument [Line Items]
Fair value adjustment	4,000,000	4,000,000								4,700,000
CEQP Credit Facility | Line of Credit, Excluding Bridge Loans | Minimum
Debt Instrument [Line Items]
Contingent margin	0.75%	0.75%
CEQP Credit Facility | Line of Credit, Excluding Bridge Loans | Maximum
Debt Instrument [Line Items]
Contingent margin	2.00%	2.00%
CEQP Credit Facility | Revolving Credit Facility | Minimum | London Interbank Offered Rate
Debt Instrument [Line Items]
Weighted average interest rate	3.02%	3.02%								2.68%
CEQP Credit Facility | Revolving Credit Facility | Line of Credit | Amended and Restated
Debt Instrument [Line Items]
Credit agreement outstanding carrying value	495,000,000	495,000,000													625,000,000	625,000,000	550,000,000
Total funded debt to consolidated EBITDA		5.5
CEQP Credit Facility | Bridge Loan | Line of Credit
Debt Instrument [Line Items]
Debt issuance costs				1,700,000
CEQP Credit Facility | Bridge Loan | Line of Credit | Amended and Restated
Debt Instrument [Line Items]
Credit agreement outstanding carrying value																25,000,000	100,000,000
Obligations Under Noncompetition Agreements And Notes To Former Owners Of Businesses Acquired
Debt Instrument [Line Items]
Total payments due	7,400,000	7,400,000
Obligations under noncompete agreements, unamortized discount	$1,300,000	$1,300,000
Obligations Under Noncompetition Agreements And Notes To Former Owners Of Businesses Acquired | Minimum
Debt Instrument [Line Items]
Inputed interest	5.02%	5.02%
Obligations Under Noncompetition Agreements And Notes To Former Owners Of Businesses Acquired | Maximum
Debt Instrument [Line Items]
Inputed interest	8.00%	8.00%
Alternate Base Rate | Crestwood Midstream Revolver | Swing Line Loans | Minimum
Debt Instrument [Line Items]
Variable interest rate		0.75%
Alternate Base Rate | Crestwood Midstream Revolver | Swing Line Loans | Maximum
Debt Instrument [Line Items]
Variable interest rate		1.75%
Federal Funds Rate | Crestwood Midstream Revolver | Line of Credit, Excluding Bridge Loans
Debt Instrument [Line Items]
Variable interest rate		0.50%
Adjusted London Interbank Offered Rate | Crestwood Midstream Revolver | Line of Credit, Excluding Bridge Loans
Debt Instrument [Line Items]
Variable interest rate		1.00%
London Interbank Offered Rate | Crestwood Midstream Revolver | Line of Credit, Excluding Bridge Loans | Minimum
Debt Instrument [Line Items]
Variable interest rate		1.75%
London Interbank Offered Rate | Crestwood Midstream Revolver | Line of Credit, Excluding Bridge Loans | Maximum
Debt Instrument [Line Items]
Variable interest rate		2.75%
London Interbank Offered Rate | CEQP Credit Facility | Line of Credit, Excluding Bridge Loans | Minimum
Debt Instrument [Line Items]
Variable interest rate		1.75%
London Interbank Offered Rate | CEQP Credit Facility | Line of Credit, Excluding Bridge Loans | Maximum
Debt Instrument [Line Items]
Variable interest rate		3.00%
Scenario, Forecast | CEQP Credit Facility | Revolving Credit Facility | Line of Credit | Amended and Restated
Debt Instrument [Line Items]
Total funded debt to consolidated EBITDA					4.75	5	5.25
Tres Palacios Holdings LLC
Debt Instrument [Line Items]
Equity method ownership percentage	50.01%	50.01%
Tres Palacios Holdings LLC | CMLP
Debt Instrument [Line Items]
Equity method ownership percentage	50.01%	50.01%

LongTerm_Debt_Maturities_of_Lo

Long-Term Debt (Maturities of Long Term Debt) (Details) (USD $)	Dec. 31, 2014
In Millions, unless otherwise specified
Debt Disclosure [Abstract]
2015	$3.70
2016	367.9
2017	0.9
2018	566.1
2019	350.9
Thereafter	1,102
Total debt	$2,391.50

Earnings_Per_Limited_Partner_U1

Earnings Per Limited Partner Unit (Schedule of Reconciliation of Earnings Per Share) (Details)	12 Months Ended
	Dec. 31, 2014
Earnings Per Share [Abstract]
Antidilutive securities excluded from computation of earnings per share	0

Income_Taxes_Details

Income Taxes (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Current:
Federal	$5	$2.50	$0
State	1.3	1.3	1.2
Total current	6.3	3.8	1.2
Deferred:
Federal	-5.3	-2.5	0
State	0.1	-0.3	0
Total deferred	-5.2	-2.8	0
Provision for income taxes	1.1	1	1.2
Deferred tax liability:
Basis difference in stock of acquired company	-12	-17.2
Total deferred tax liability	($12)	($17.20)

Partners_Capital_Schedule_of_I

Partners' Capital (Schedule of Issuance of Units) (Details) (Unit Distribution, USD $)	0 Months Ended
In Millions, except Share data, unless otherwise specified	Oct. 24, 2013	Sep. 13, 2013	Mar. 22, 2013	Jul. 25, 2012	Jan. 13, 2012	Oct. 30, 2013	Oct. 23, 2013	Oct. 07, 2013	Apr. 30, 2013	Aug. 31, 2012
Unit Distribution
Distribution Made to Member or Limited Partner [Line Items]
Units		11,773,191	5,175,000	4,600,000	3,500,000	2,100,000	16,100,000	773,191	675,000	600,000
Per Unit Gross Price		$22.50	$23.90	$26	$30.73
Per Unit Net Price		$21.69	$23	$24.97	$29.50		$21.19
Net Proceeds	$340.30	$255.20	$118.50	$114.40	$103.10

Partners_Capital_Narrative_Det

Partners' Capital (Narrative) (Details) (USD $)

0 Months Ended

1 Months Ended

3 Months Ended

12 Months Ended

0 Months Ended

1 Months Ended

0 Months Ended

1 Months Ended

0 Months Ended

3 Months Ended

0 Months Ended

Jul. 18, 2014

Jul. 10, 2014

Jun. 17, 2014

Oct. 26, 2013

Jan. 08, 2013

Feb. 29, 2012

Dec. 31, 2014

Sep. 30, 2014

Jun. 30, 2014

Mar. 31, 2014

Sep. 30, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2012

Feb. 13, 2015

Aug. 31, 2012

6-May-13

Oct. 07, 2013

Nov. 08, 2013

Oct. 31, 2013

Jan. 30, 2015

Mar. 31, 2013

Oct. 24, 2013

Sep. 14, 2012

Distribution Made to Member or Limited Partner [Line Items]

Distribution to limited partner, distribution date

14-Nov-13

14-Nov-14

14-Aug-14

15-May-14

14-Feb-14

14-Aug-13

Net proceeds from the issuance of Crestwood Midstream Partners LP Class A preferred units

$430,500,000

Maximum Period For Distribution Of Available Cash

45 days

Per unit rate, in dollars per unit

$0.14

$0.14

$0.14

$0.14

$0.14

$0.13

Distributions to partners

-102,500,000

-68,400,000

-13,800,000

Investment in unconsolidated affiliates in period

131,300,000

108,600,000

151,500,000

0

Equity method ownership percentage

35.00%

Percentage of voting interests acquired

65.00%

99.00%

Consideration transferred

258,000,000

Loss on contingent consideration

-8,600,000

-31,400,000

6,800,000

Contribution from issuance of units

26,299,076

300,000,000

500,000,000

17,529,879

714,000,000

217,500,000

Equity Distribution Agreement Management Fee Percent

2.00%

Distribution made to limited partners

387,991

633,084

Net Income (Loss) Attributable to Noncontrolling Interest

-66,800,000

-57,300,000

9,500,000

Issuance of preferred equity of subsidiary

53,900,000

96,100,000

Partners' Capital, Distribution Amount Per Share

$0.58

$0.58

Partners' Capital Account, Private Placement of Units, Price Per Unit

$25.10

$25.10

Partners' Capital, Contingent Distribution Amount Per Share

$0.71

$0.71

Partner's Capital, Unpaid Distribution, Accrual Percentage

2.81%

Proceeds from Issuance of Preferred Limited Partners Units, Gross

440,000,000

Distribution to limited partner, record date

7-Nov-13

7-Nov-14

7-Aug-14

8-May-14

7-Feb-14

7-Aug-13

Partners' Capital Account, Acquisitions

0

Preferred Units, Class C

Distribution Made to Member or Limited Partner [Line Items]

Distribution made to limited partners

183,995

Preferred Units, Class D

Distribution Made to Member or Limited Partner [Line Items]

Distribution made to limited partners

6,190,469

292,660

Preferred Units, Class A

Distribution Made to Member or Limited Partner [Line Items]

Partners' Capital Account, Private Placement of Units, Price Per Unit

$25.10

General Partner

Distribution Made to Member or Limited Partner [Line Items]

Distribution made to limited partners

133,060

Subsequent Event

Distribution Made to Member or Limited Partner [Line Items]

Distribution made to limited partners

414,325

Suburban Propane Partners L P [Member]

Distribution Made to Member or Limited Partner [Line Items]

Limited Liability Company L L C Or Limited Partnership L P Members Or Limited Partners Ownership Interest Shares

142,000

Legacy Crestwood

Distribution Made to Member or Limited Partner [Line Items]

Net proceeds from the issuance of Crestwood Midstream Partners LP Class A preferred units

5,900,000

Partners' Capital Account, Units, Sale of Units

215,722

Incentive Distribution, Distribution

9,300,000

13,800,000

Crestwood Holdings

Distribution Made to Member or Limited Partner [Line Items]

Cash payments to unitholders upon completion of merger

10,000,000

Investment in unconsolidated affiliates in period

243,800,000

Crestwood Niobrara LLC

Distribution Made to Member or Limited Partner [Line Items]

Net Income (Loss) Attributable to Noncontrolling Interest

16,800,000

4,900,000

0

Issuance of preferred equity of subsidiary

150,000,000

CMLP

Distribution Made to Member or Limited Partner [Line Items]

Conversion ratio

1.07

CMLP

Distribution Made to Member or Limited Partner [Line Items]

Cash

34,900,000

Distributions to partners

-11,800,000

Arrow Midstream Holdings, LLC

Distribution Made to Member or Limited Partner [Line Items]

Cash

550,000,000

Consideration transferred

750,000,000

Business Acquisition, Equity Interest Issued or Issuable, Number of Shares

8,826,125

Contribution from issuance of units

200,000,000

Legacy Crestwood

Distribution Made to Member or Limited Partner [Line Items]

Contingent consideration, liability

72,000,000

Loss on contingent consideration

6,800,000

Payments for Previous Acquisition

41,100,000

Jackalope Gas Gathering Services, LLC | Preferred Units

Distribution Made to Member or Limited Partner [Line Items]

Distribution made to limited partners

11,419,241

2,161,657

Jackalope Gas Gathering Services, LLC | Subsequent Event | Preferred Units

Distribution Made to Member or Limited Partner [Line Items]

Distribution made to limited partners

3,680,570

Jackalope Gas Gathering Services, LLC | Crestwood Niobrara LLC

Distribution Made to Member or Limited Partner [Line Items]

Investment in unconsolidated affiliates in period

105,200,000

19,600,000

Legacy Crestwood Credit Facility

Distribution Made to Member or Limited Partner [Line Items]

Consideration transferred

129,000,000

Cash distribution

Distribution Made to Member or Limited Partner [Line Items]

Distribution to limited partner, distribution date

13-Feb-15

Distribution declared per limited partner unit

$296,500,000

$179,600,000

$89,700,000

Distribution to limited partner, record date

6-Feb-15

Cash distribution | Subsequent Event

Distribution Made to Member or Limited Partner [Line Items]

Distribution declared per limited partner unit

0.1375

Subordinated Unit | Limited Partners

Distribution Made to Member or Limited Partner [Line Items]

Partners' Capital Account, Units, Period Increase (Decrease)

4,387,889

Partners' Capital Account, Units, Cash Distribution Threshold, Quarterly Distribution

$0.13

Partners' Capital Account, Units, Conversion Threshold, Cumulative Distribution

$0.52

Crestwood Holdings | Crestwood Equity Partners LP

Distribution Made to Member or Limited Partner [Line Items]

Shares issued by acquiree

14,300,000

Crestwood Holdings | Majority Shareholder

Distribution Made to Member or Limited Partner [Line Items]

Shares exchanged by acquirer

7,100,000

Non-Controlling Partners

Distribution Made to Member or Limited Partner [Line Items]

Contribution from issuance of units

714,000,000

217,500,000

Issuance of preferred equity of subsidiary

53,900,000

96,100,000

Partners' Capital Account, Acquisitions

-182,300,000

Non-Controlling Partners | Arrow Midstream Holdings, LLC

Distribution Made to Member or Limited Partner [Line Items]

Contribution from issuance of units

200,000,000

Limited Partners

Distribution Made to Member or Limited Partner [Line Items]

Contribution from issuance of units

0

0

Issuance of preferred equity of subsidiary

0

0

Partners' Capital Account, Acquisitions

182,300,000

Limited Partners | Arrow Midstream Holdings, LLC

Distribution Made to Member or Limited Partner [Line Items]

Contribution from issuance of units

$0

Partners_Capital_Schedule_of_P

Partners' Capital (Schedule of Partnership Distributions) (Details) (USD $)	0 Months Ended	3 Months Ended					12 Months Ended		0 Months Ended	12 Months Ended	0 Months Ended
In Millions, except Per Share data, unless otherwise specified	Oct. 26, 2013	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Sep. 30, 2013	Dec. 31, 2014	Dec. 31, 2013	Oct. 24, 2013	Dec. 31, 2012	Feb. 13, 2015
Disclosure Partners Capital Summary Of Quarterly Distributions Of Available Cash [Abstract]
Distribution to limited partner, record date	7-Nov-13	7-Nov-14	7-Aug-14	8-May-14	7-Feb-14	7-Aug-13
Distribution to limited partner, distribution date	14-Nov-13	14-Nov-14	14-Aug-14	15-May-14	14-Feb-14	14-Aug-13
Distribution Made to Limited Partner, Distributions Paid, Per Unit	$0.14	$0.14	$0.14	$0.14	$0.14	$0.13
Distribution amount	$25	$25.60	$25.60	$25.70	$25.60	$22.30	$47.30	$102.50
Cash distribution
Disclosure Partners Capital Summary Of Quarterly Distributions Of Available Cash [Abstract]
Distribution to limited partner, record date									6-Feb-15
Distribution to limited partner, distribution date									13-Feb-15
Distribution declared per limited partner unit							$296,500,000	$179,600,000		$89,700,000
Cash distribution | Subsequent Event
Disclosure Partners Capital Summary Of Quarterly Distributions Of Available Cash [Abstract]
Distribution declared per limited partner unit											$0.14
Legacy Crestwood
Disclosure Partners Capital Summary Of Quarterly Distributions Of Available Cash [Abstract]
Incentive Distribution, Distribution								$9.30		$13.80

Partners_Capital_Net_Income_Lo

Partners' Capital Net Income (Loss) Attributable to NonControlling Partners (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Limited Partners' Capital Account [Line Items]
Net Income (Loss) Attributable to Noncontrolling Interest	($66.80)	($57.30)	$9.50
CMLP
Limited Partners' Capital Account [Line Items]
Net Income (Loss) Attributable to Noncontrolling Interest	-100.8	-62.2	9.5
CMLP | Preferred Units, Class A
Limited Partners' Capital Account [Line Items]
Net Income (Loss) Attributable to Noncontrolling Interest	17.2	0	0
Crestwood Niobrara LLC
Limited Partners' Capital Account [Line Items]
Net Income (Loss) Attributable to Noncontrolling Interest	$16.80	$4.90	$0

Equity_Plans_Narrative_Details

Equity Plans (Narrative) (Details) (USD $)	12 Months Ended			1 Months Ended
In Millions, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jan. 31, 2015	Feb. 13, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employer match, percent of deferrals	10.00%
Units purchased under plan	15,369
Compensation expense	$10.10	$10.90
Employer matching contribution, percent	6.00%
Phantom and Restricted Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants of units, estimated grant date fair value		4.6	4.7
Compensation expense		6.5	1.9
Crestwood Long-Term Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common units to satisfy employee tax withholding obligations	159,435	362,565
Crestwood Long-Term Incentive Plan | Restricted units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation costs not yet recognized	8.1	1.6
Grants of units, estimated grant date fair value	18.2
Crestwood Midstream Long-Term Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated share based compensation expense	11.2	11.4
Common units to satisfy employee tax withholding obligations	71,484	21,014
Crestwood Midstream Long-Term Incentive Plan | Restricted units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants of units, estimated grant date fair value	20.3
Shares reserved for future issuance	17,629,657
Employee Unit Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum annual contributions per employee, percent	10.00%
Employer matching contribution, percent	10.00%
Maximum purchasable units	200,000
CMLP | Crestwood Long-Term Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated share based compensation expense	6.9	4.4
CMLP | Crestwood Midstream Long-Term Incentive Plan | Restricted units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation costs not yet recognized	$9.50	$1.80
Subsequent Event
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued in the period				10,000,000
Units of partnership interest, amount				15,000,000
Subsequent Event | Crestwood Long-Term Incentive Plan | Restricted units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for future issuance					12,613,231
Subsequent Event | Employee Unit Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units purchased under plan				2,011

Equity_Plans_Schedule_of_Phant

Equity Plans (Schedule of Phantom and Restricted Unit Activity) (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2012
Phantom and Restricted Units | Payable In Cash
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Unvested units - December 31, units			8,312
Unvested units - December 31			$26.45
Unvested units - December 31, units	0		8,312
Unvested units - December 31	$0		$26.45
Phantom and Restricted Units | Payable In Units
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Unvested units - December 31, units			221,992
Unvested units - December 31			$28.35
Unvested units - December 31, units	0		221,992
Unvested units - December 31	$0		$28.35
Restricted units | Payable In Cash
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Vested, units	0
Vested	$0
Granted, units	0
Granted	$0
Restricted units | Payable In Units
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Vested, units	-74,760
Vested	$25.60
Granted, units	27,900
Granted	$24.86
Phantom Share Units (PSUs) | Payable In Cash
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Vested, units	-7,958
Vested	$26.48
Granted, units	0
Granted	$0
Canceled, units	-354
Canceled	$25.81
Phantom Share Units (PSUs) | Payable In Units
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Vested, units	-329,825
Vested	$26.69
Granted, units	161,807
Granted	$24.33
Canceled, units	-7,114
Canceled	$27.96
Crestwood Midstream Long-Term Incentive Plan | Restricted units
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Unvested units - December 31, units		250,557
Unvested units - December 31		$22.13
Vested, units		-208,361
Vested		$22.15
Granted, units		871,078
Granted		$23.25
Canceled, units		-78,478
Canceled		$23.33
Unvested units - December 31, units		834,796
Unvested units - December 31		$23.18
Crestwood Long-Term Incentive Plan | Restricted units
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Unvested units - December 31, units		493,543
Unvested units - December 31		$13.96
Vested, units		-449,936
Vested		$13.97
Granted, units		1,377,461
Granted		$13.23
Canceled, units		-105,188
Canceled		$13.73
Unvested units - December 31, units		1,315,880
Unvested units - December 31		$13.21

Employee_Benefit_Plan_Details

Employee Benefit Plan (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Postemployment Benefits [Abstract]
Defined Contribution Plan, Employer Matching Contribution, Percent	75.00%
Defined Benefit Plan, Employee Contributions, Statutory Maximum Per Employee	$17,500	$17,500,000,000
Defined Contribution Plan Participants Basic Contribution	100.00%
Employer matching contribution, percent	6.00%
Defined Contribution Plan, Requisite Service Period	90 days
Defined Benefit Plan, Contributions by Employer	$3,800,000	$500,000

Commitments_and_Contingencies_1

Commitments and Contingencies (Narrative) (Details) (USD $)	12 Months Ended			1 Months Ended
In Millions, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Mar. 31, 2014	Nov. 08, 2013
				defendant	bbl
					people
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Capital Lease Obligations, Noncurrent	$5.30	$4.70
Loss Contingency Accrual, at Carrying Value	1	0.1
Operations and maintenance	203.3	104.6	43.1
Accrual for Environmental Loss Contingencies	1.1
Self-insurance reserves	14.6	15.8
Self-insurance reserve expected to be paid in next fiscal year	9.7
Arrow Acquisition Class Action Lawsuit
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Barrels of Oil Equivalents Spilled					50,000
Loss Contingency, Loss of Life, Number					47
Loss Contingency, Number of Defendants				53
Escrow Deposit of Common Units	3,309,797
Number of putative class action lawsuits	3
Identified Growth Projects
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Firm Purchase Commitments	22.7
Other Growth and Maintenance Contractual Purchase Obligations
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Firm Purchase Commitments	9.8
Commodity
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Firm Purchase Commitments	242.9
Fort Berthold Indian Reservation
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Site Contingency, Loss Exposure, Number of Releases of Produced Water	3
Site Contingency, Loss Exposure, Release of Produced Water	28,000
Operations and maintenance	4.6
Total current liabilities	1.1
Pending Litigation | Matagorda County Appraisal District
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Loss Contingency, Estimate of Possible Loss	12
Minimum
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Accrual for Environmental Loss Contingencies	1.1
Maximum
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Accrual for Environmental Loss Contingencies	$1.50

Commitments_and_Contingencies_2

Commitments and Contingencies (Schedule of Future Minimum Lease Payments under Noncancelable Operatng Leases) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Commitments and Contingencies Disclosure [Abstract]
2015	$16.90
2016	15.5
2017	12.9
2018	11
2019	9.9
Thereafter	17.5
Operating Leases, Future Minimum Payments Due	83.7
Rent expense	$41.80	$16.40	$7.40

Commitments_and_Contingencies_3

Commitments and Contingencies (Schedule of Future Minimum Lease Payments Related to Capital Leases) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Commitments and Contingencies Disclosure [Abstract]
Capital Leases, Income Statement, Amortization Expense	$3.30	$3.60	$3.10
2015	2.2
2016	1.6
2017	1.2
2018	0.4
Total payments	5.4
Imputed interest	-0.1
Present value of future payments	5.3
Capital Lease Obligations, Noncurrent	$5.30	$4.70

Related_Party_Transactions_Det

Related Party Transactions (Details) (USD $)	12 Months Ended			0 Months Ended
In Millions, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Oct. 07, 2013
Related Party Transaction [Line Items]
Gathering and processing revenues	$3	$74.90	$113.70
Affiliated Entity
Related Party Transaction [Line Items]
Gathering and processing revenues	3	74.9
Gathering and processing costs of product/services sold(2)	42.2	32.5
General and administrative expenses	0.5	25.3
Related Party Transaction, Due from (to) Related Party [Abstract]
Accounts receivable	0.6	0
Accounts payable	5.6	3.6
Crestwood Equity Partners LP
Related Party Transaction [Line Items]
Gathering and processing revenues			113.7
Gathering and processing costs of product/services sold(2)			15.2
General and administrative expenses			$19.50
Crestwood Holdings | Majority Shareholder
Related Party Transaction, Due from (to) Related Party [Abstract]
Shares exchanged by acquirer				7,100,000
Crestwood Equity Partners LP | Crestwood Holdings
Related Party Transaction, Due from (to) Related Party [Abstract]
Shares issued by acquiree				14,300,000

Segments_Narrative_Details

Segments (Narrative) (Details) (USD $)	3 Months Ended								12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
									segment
Segment Reporting [Abstract]
Number of operating segments									3
Revenue, Major Customer [Line Items]
Revenues	$997.20	$1,036.20	$926.30	$971.60	$808.20	$427.20	$118.90	$72.40	$3,931.30	$1,426.70	$239.50
Concentration Risk, Percentage									10.00%
Tesoro
Revenue, Major Customer [Line Items]
Revenues									465.2
Quicksilver
Revenue, Major Customer [Line Items]
Revenues											112.6
Antero
Revenue, Major Customer [Line Items]
Revenues											$25.50

Segments_Reconciliation_of_Net

Segments (Reconciliation of Net Income (Loss) to EBITDA) (Details) (USD $)	3 Months Ended								12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Segment Reporting [Abstract]
Net income (loss)	($30.70)	$11.90	($4.80)	$13.20	($42.10)	($7.90)	($4.50)	$3.90	($10.40)	($50.60)	$24.40
Interest Expense									127.1	77.9	35.8
Provision for income taxes									1.1	1	1.2
Depreciation, amortization and accretion									285.3	167.9	73.2
EBITA									$403.10	$196.20	$134.60

Segments_Summary_Of_Segment_In

Segments (Summary Of Segment Information) (Details) (USD $)	3 Months Ended								12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jun. 19, 2013
Operating revenues	$997.20	$1,036.20	$926.30	$971.60	$808.20	$427.20	$118.90	$72.40	$3,931.30	$1,426.70	$239.50
Cost of Goods and Services Sold									3,165.30	1,002.30	-39
Operations and maintenance									203.3	104.6	43.1
General and administrative (Note 16)									100.2	93.5	29.6
Gain (loss) on long-lived assets, net									-1.9	5.3	0
Goodwill impairment									-48.8	-4.1	0
Gain (loss) on contingent consideration (Note 15)									-8.6	-31.4	6.8
Earnings (loss) from unconsolidated affiliates, net	0.6	0.3	-1.5	-0.1	0.3	-0.4	0	0	-0.7	-0.1	0
Other income, net									0.6	0.2	0
EBITA									403.1	196.2	134.6
Goodwill	2,491.80				2,552.20				2,491.80	2,552.20	352.2	2,134.80
Assets	8,461.40				8,523.20				8,461.40	8,523.20	2,301.60
Payments to Acquire Property, Plant, and Equipment									424	347	52.6
Gathering and Processing Operations
Operating revenues									332.5	291.2	239.5
Cost of Goods and Services Sold									71.3	56.6	-39
Operations and maintenance									62.9	54.9	43.1
General and administrative (Note 16)									0	0	0
Gain (loss) on long-lived assets, net									-32.7	5.4
Goodwill impairment									-18.5	-4.1
Gain (loss) on contingent consideration (Note 15)									-8.6	-31.4	6.8
Earnings (loss) from unconsolidated affiliates, net									0.5	0.1
Other income, net									0	0
EBITA									139	149.7	164.2
Goodwill	338.3				356.8				338.3	356.8	352.2
Assets	2,645				2,507.30				2,645	2,507.30	2,278.90
Payments to Acquire Property, Plant, and Equipment									245.7	271.2	51.5
Storage and Transportation
Operating revenues									192.9	104.2	0
Cost of Goods and Services Sold									24.8	15.7	0
Operations and maintenance									23.3	12.1	0
General and administrative (Note 16)									0	0	0
Gain (loss) on long-lived assets, net									33.8	0
Goodwill impairment									0	0
Gain (loss) on contingent consideration (Note 15)									0	0	0
Earnings (loss) from unconsolidated affiliates, net									0.2	0
Other income, net									0	0
EBITA									178.8	76.4	0
Goodwill	726.3				936.5				726.3	936.5	0
Assets	1,981.20				2,369.10				1,981.20	2,369.10	0
Payments to Acquire Property, Plant, and Equipment									9.7	18	0
Crude Oil and NGL
Operating revenues									3,406.90	1,031.30	0
Cost of Goods and Services Sold									3,070.20	930	0
Operations and maintenance									117.1	37.6	0
General and administrative (Note 16)									0	0	0
Gain (loss) on long-lived assets, net									-3	-0.1
Goodwill impairment									-30.3	0
Gain (loss) on contingent consideration (Note 15)									0	0	0
Earnings (loss) from unconsolidated affiliates, net									-1.4	-0.2
Other income, net									0	0
EBITA									184.9	63.4	0
Goodwill	1,427.20				1,258.90				1,427.20	1,258.90	0
Assets	3,631.30				3,465.80				3,631.30	3,465.80	0
Payments to Acquire Property, Plant, and Equipment									160.4	56.8	0
Intersegment Eliminations
Operating revenues									-1	0	0
Cost of Goods and Services Sold									-1	0	0
Operations and maintenance									0	0	0
General and administrative (Note 16)									0	0	0
Gain (loss) on long-lived assets, net									0	0
Goodwill impairment									0	0
Gain (loss) on contingent consideration (Note 15)									0	0	0
Earnings (loss) from unconsolidated affiliates, net									0	0
Other income, net									0	0
EBITA									0	0	0
Goodwill	0				0				0	0	0
Assets	0				0				0	0	0
Payments to Acquire Property, Plant, and Equipment									0	0	0
Corporate
Operating revenues									0	0	0
Cost of Goods and Services Sold									0	0	0
Operations and maintenance									0	0	0
General and administrative (Note 16)									100.2	93.5	29.6
Gain (loss) on long-lived assets, net									0	0
Goodwill impairment									0	0
Gain (loss) on contingent consideration (Note 15)									0	0	0
Earnings (loss) from unconsolidated affiliates, net									0	0
Other income, net									0.6	0.2
EBITA									-99.6	-93.3	-29.6
Goodwill	0				0				0	0	0
Assets	203.9				181				203.9	181	22.7
Payments to Acquire Property, Plant, and Equipment									$8.20	$1	$1.10

Condensed_Consolidating_Financ2

Condensed Consolidating Financial Information (Cash Flow Adjustments to Prior Periods) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Net cash provided by operating activities	$283	$188.30	$102.10
Net cash used in investing activities	-483	-1,042.90	-616.6
Proceeds from the issuance of long-term debt	2,823.90	2,466.90	706.7
Principal payments on long-term debt	-2,696	-1,967.60	-534
Distributions to partners	-102.5	-68.4	-13.8
Change in intercompany balances		0
Other	-0.7	0.1	0
Net cash provided by financing activities	203.6	859.7	513.8
Parent Company
Net cash provided by operating activities	-25.3	-12.3	0
Capital contributions from consolidated affiliates, net and other		20.7
Net cash used in investing activities	170.8	20.7	-146.2
Proceeds from the issuance of long-term debt	734	394.1	0
Principal payments on long-term debt	-746.2	-333.3	0
Distributions to partners	-102.5	-68.4	-103.5
Change in intercompany balances	-25.4	0.4	0
Other	0	-1.1	0
Net cash provided by financing activities	-141.9	-8.3	146.2
Parent Company | As Previously Reported
Net cash provided by operating activities		0
Capital contributions from consolidated affiliates, net and other		76
Net cash used in investing activities		76
Proceeds from the issuance of long-term debt		0
Principal payments on long-term debt		0
Distributions to partners		-76
Change in intercompany balances		0
Other		0.1
Net cash provided by financing activities		-75.9
Guarantor Subsidiaries
Net cash provided by operating activities	-14.6	14.1
Capital contributions from consolidated affiliates, net and other		0.1
Net cash used in investing activities	-10.5	-6.4
Proceeds from the issuance of long-term debt	0	0
Principal payments on long-term debt	0	0
Distributions to partners	0	0
Change in intercompany balances	25.4	-0.4
Other	0.1	-4.9
Net cash provided by financing activities	23.2	-5.3
Guarantor Subsidiaries | As Previously Reported
Net cash provided by operating activities		1.8
Capital contributions from consolidated affiliates, net and other		17
Net cash used in investing activities		10.5
Proceeds from the issuance of long-term debt		394.1
Principal payments on long-term debt		-333.3
Distributions to partners		-59.1
Change in intercompany balances		0
Other		-11.6
Net cash provided by financing activities		-9.9
Consolidation, Eliminations
Net cash provided by operating activities	0	0
Capital contributions from consolidated affiliates, net and other		-20.7
Net cash used in investing activities	-72.4	-20.7
Proceeds from the issuance of long-term debt	0	0
Principal payments on long-term debt	0	0
Distributions to partners	72.4	26.2
Change in intercompany balances	0	0
Other	0	-5.5
Net cash provided by financing activities	72.4	20.7
Consolidation, Eliminations | As Previously Reported
Net cash provided by operating activities		0
Capital contributions from consolidated affiliates, net and other		-92.9
Net cash used in investing activities		-92.9
Proceeds from the issuance of long-term debt		0
Principal payments on long-term debt		0
Distributions to partners		92.9
Change in intercompany balances		0
Other		0
Net cash provided by financing activities		$92.90

Condensed_Consolidating_Financ3

Condensed Consolidating Financial Information (Balance Sheet) (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jun. 30, 2012	Dec. 31, 2011
Current assets:
Cash	$8,800,000	$5,200,000	$100,000		$800,000
Total accounts receivable	379,600,000	412,600,000
Total current assets	538,100,000	522,000,000
Property, plant and equipment, net	3,893,800,000	3,905,300,000
Investment in unconsolidated affiliates	295,100,000	151,400,000
Other assets	11,300,000	31,900,000
Total assets	8,461,400,000	8,523,200,000	2,301,600,000
Current liabilities:
Total accounts payable	241,200,000	379,000,000
Total current liabilities	424,900,000	596,100,000
Long-term liabilities:
Long-term debt, less current portion (Note 7)	2,392,800,000	2,260,900,000
Other long-term liabilities	47,200,000	140,400,000
Total partners’ capital	5,584,500,000	5,508,600,000	1,550,700,000		1,120,000,000
Total liabilities and partners’ capital	8,461,400,000	8,523,200,000
Parent Company
Current assets:
Cash	3,700,000	100,000	0	100,000	0
Accounts receivable	0
Accounts receivable - related party	0
Accounts receivable - intercompany	3,200,000	0		0
Total accounts receivable	3,200,000	0
Inventory	0	0
Other	0	0
Total current assets	6,900,000	100,000		100,000
Property, plant and equipment, net	2,500,000	0		0
Intangible assets	1,700,000	0		0
Investment in consolidated affiliates	5,971,200,000	5,927,100,000		5,927,100,000
Investment in unconsolidated affiliates	0	0
Other assets	0	0
Total assets	5,982,300,000	5,927,200,000		5,927,200,000
Current liabilities:
Accounts payable	0	0
Accounts payable - related party	0	0
Accounts payable - intercompany	0	0
Total accounts payable	0	0
Total current liabilities	4,900,000	4,200,000		4,200,000
Total current liabilities	4,900,000	4,200,000
Long-term liabilities:
Long-term debt, less current portion (Note 7)	380,000,000	393,000,000		393,000,000
Other long-term liabilities	12,900,000	21,400,000		21,400,000
Total long-term liabilities	392,900,000	414,400,000
Partners' capital	776,200,000	831,600,000
Interest of non-controlling partners in subsidiary	4,808,300,000	4,677,000,000
Total partners’ capital	5,584,500,000	5,508,600,000		5,508,600,000
Total liabilities and partners’ capital	5,982,300,000	5,927,200,000		5,927,200,000
Guarantor Subsidiaries
Current assets:
Cash	500,000	2,400,000	0
Accounts receivable	137,500,000	207,500,000
Accounts receivable - related party	300,000
Accounts receivable - intercompany	0	0
Total accounts receivable	137,800,000	207,500,000
Inventory	38,600,000	66,600,000
Other	84,400,000	25,800,000
Total current assets	261,300,000	302,300,000
Property, plant and equipment, net	227,100,000	400,900,000
Intangible assets	706,700,000	742,400,000
Investment in consolidated affiliates	0	0
Investment in unconsolidated affiliates	0	0
Other assets	9,900,000	10,200,000
Total assets	1,205,000,000	1,455,800,000
Current liabilities:
Accounts payable	109,500,000	218,300,000
Accounts payable - related party	2,500,000	0
Accounts payable - intercompany	0	0
Total accounts payable	112,000,000	218,300,000
Total current liabilities	56,100,000	61,600,000
Total current liabilities	168,100,000	279,900,000
Long-term liabilities:
Long-term debt, less current portion (Note 7)	0	0
Other long-term liabilities	15,100,000	109,900,000
Total long-term liabilities	15,100,000	109,900,000
Partners' capital	1,021,800,000	1,066,000,000
Interest of non-controlling partners in subsidiary	0	0
Total partners’ capital	1,021,800,000	1,066,000,000
Total liabilities and partners’ capital	1,205,000,000	1,455,800,000
Non-Guarantor Subsidiaries
Current assets:
Cash	4,600,000	2,700,000	100,000
Accounts receivable	241,500,000	205,100,000
Accounts receivable - related party	300,000
Accounts receivable - intercompany	0	0
Total accounts receivable	241,800,000	205,100,000
Inventory	8,000,000	7,000,000
Other	18,700,000	10,200,000
Total current assets	273,100,000	225,000,000
Property, plant and equipment, net	3,664,200,000	3,504,400,000
Intangible assets	3,014,700,000	3,170,200,000
Investment in consolidated affiliates	0	0
Investment in unconsolidated affiliates	295,100,000	151,400,000
Other assets	1,400,000	21,700,000
Total assets	7,248,500,000	7,072,700,000
Current liabilities:
Accounts payable	126,100,000	157,100,000
Accounts payable - related party	3,100,000	3,600,000
Accounts payable - intercompany	3,200,000	0
Total accounts payable	132,400,000	160,700,000
Total current liabilities	122,700,000	156,700,000
Total current liabilities	255,100,000	317,400,000
Long-term liabilities:
Long-term debt, less current portion (Note 7)	2,012,800,000	1,867,900,000
Other long-term liabilities	31,200,000	26,300,000
Total long-term liabilities	2,044,000,000	1,894,200,000
Partners' capital	141,100,000	184,100,000
Interest of non-controlling partners in subsidiary	4,808,300,000	4,677,000,000
Total partners’ capital	4,949,400,000	4,861,100,000
Total liabilities and partners’ capital	7,248,500,000	7,072,700,000
Consolidation, Eliminations
Current assets:
Cash	0	0	0
Accounts receivable	0	0
Accounts receivable - related party	0
Accounts receivable - intercompany	-3,200,000	0
Total accounts receivable	-3,200,000	0
Inventory	0	0
Other	0	-5,400,000
Total current assets	-3,200,000	-5,400,000
Property, plant and equipment, net	0	0
Intangible assets	0	0
Investment in consolidated affiliates	-5,971,200,000	-5,927,100,000
Investment in unconsolidated affiliates	0	0
Other assets	0	0
Total assets	-5,974,400,000	-5,932,500,000
Current liabilities:
Accounts payable	0	0
Accounts payable - related party	0	0
Accounts payable - intercompany	-3,200,000	0
Total accounts payable	-3,200,000	0
Total current liabilities	0	-5,400,000
Total current liabilities	-3,200,000	-5,400,000
Long-term liabilities:
Long-term debt, less current portion (Note 7)	0	0
Other long-term liabilities	0	0
Total long-term liabilities	0	0
Partners' capital	-1,162,900,000	-1,250,100,000
Interest of non-controlling partners in subsidiary	-4,808,300,000	-4,677,000,000
Total partners’ capital	-5,971,200,000	-5,927,100,000
Total liabilities and partners’ capital	-5,974,400,000	-5,932,500,000
Consolidated Entities
Current assets:
Cash	8,800,000	5,200,000	100,000
Accounts receivable	379,000,000	412,600,000
Accounts receivable - related party	600,000
Accounts receivable - intercompany	0	0
Total accounts receivable	379,600,000	412,600,000
Inventory	46,600,000	73,600,000
Other	103,100,000	30,600,000
Total current assets	538,100,000	522,000,000
Property, plant and equipment, net	3,893,800,000	3,905,300,000
Intangible assets	3,723,100,000	3,912,600,000
Investment in consolidated affiliates	0	0
Investment in unconsolidated affiliates	295,100,000	151,400,000
Other assets	11,300,000	31,900,000
Total assets	8,461,400,000	8,523,200,000
Current liabilities:
Accounts payable	235,600,000	375,400,000
Accounts payable - related party	5,600,000	3,600,000
Accounts payable - intercompany	0	0
Total accounts payable	241,200,000	379,000,000
Total current liabilities	183,700,000	217,100,000
Total current liabilities	424,900,000	596,100,000
Long-term liabilities:
Long-term debt, less current portion (Note 7)	2,392,800,000	2,260,900,000
Other long-term liabilities	59,200,000	157,600,000
Total long-term liabilities	2,452,000,000	2,418,500,000
Partners' capital	776,200,000	831,600,000
Interest of non-controlling partners in subsidiary	4,808,300,000	4,677,000,000
Total partners’ capital	5,584,500,000	5,508,600,000
Total liabilities and partners’ capital	$8,461,400,000	$8,523,200,000

Condensed_Consolidating_Financ4

Condensed Consolidating Financial Information (Statements Of Operations) (Details) (USD $)	3 Months Ended								12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Revenues:
Gathering and processing									$328.50	$216.30	$125.80
Storage and transportation									192.9	104.2	0
NGL and crude services									3,406.90	1,031.30	0
Related party (Note 16)									3	74.9	113.7
Total revenue	997.2	1,036.20	926.3	971.6	808.2	427.2	118.9	72.4	3,931.30	1,426.70	239.5
Costs of product/services sold:
Gathering and processing									29.1	24.1	23.8
Storage and transportation									24.8	15.7	0
NGL and crude services									3,069.20	930	0
Related party (Note 16)									42.2	32.5	15.2
Cost of product/services sold									3,165.30	1,002.30	39
Expenses:
Operations and maintenance									203.3	104.6	43.1
General and administrative									100.2	93.5	29.6
Depreciation, amortization and accretion									285.3	167.9	73.2
Goodwill impairment									-48.8	-4.1	0
Loss on contingent consideration									-8.6	-31.4	6.8
Operating income	-0.2	43	29.4	45.7	-11.1	15.8	7.8	15.7	117.9	28.2	61.4
Other income (expense):
Earnings (loss) from unconsolidated affiliates, net	0.6	0.3	-1.5	-0.1	0.3	-0.4	0	0	-0.7	-0.1	0
Interest and debt expense, net									-127.1	-77.9	-35.8
Other income, net									0.6	0.2	0
Income (loss) before income taxes									-9.3	-49.6	25.6
Provision for income taxes									1.1	1	1.2
Net income (loss)	-30.7	11.9	-4.8	13.2	-42.1	-7.9	-4.5	3.9	-10.4	-50.6	24.4
Net income attributable to non-controlling partners in subsidiary									66.8	57.3	-9.5
Net income attributable to Crestwood Equity Partners LP	38.4	2.8	-4.4	19.6	8.3	-8.3	1.6	5.1	56.4	6.7	14.9
Parent Company
Revenues:
Gathering and processing									0	0
Storage and transportation									0	0
NGL and crude services									0	0
Related party (Note 16)									0	0
Total revenue									0	0	0
Costs of product/services sold:
Gathering and processing									0	0
Storage and transportation									0	0
NGL and crude services									0	0
Related party (Note 16)									0	0
Cost of product/services sold									0	0
Expenses:
Operations and maintenance									0	0
General and administrative									8.5	0
Depreciation, amortization and accretion									0	0
Costs and Expenses									8.5	0	21.3
(Gain) loss on long-lived assets, net									0	0
Goodwill impairment									0	0
Loss on contingent consideration									0	0	6.8
Operating income									-8.5	0	-14.5
Other income (expense):
Earnings (loss) from unconsolidated affiliates, net									0	0
Interest and debt expense, net									-15.7	-6.5	0
Other income, net									0	0
Loss from unconsolidated affiliates									14.2	-43.9	38.9
Income (loss) before income taxes									-10	-50.4	24.4
Provision for income taxes									0.4	0.2	0
Net income (loss)									-10.4	-50.6	24.4
Net income attributable to non-controlling partners in subsidiary									0	0	-9.5
Net income attributable to Crestwood Equity Partners LP									-10.4	-50.6	14.9
Guarantor Subsidiaries
Revenues:
Gathering and processing									0	0
Storage and transportation									13.8	14.1
NGL and crude services									1,366.60	761.2
Related party (Note 16)									0	0
Total revenue									1,380.40	775.3
Costs of product/services sold:
Gathering and processing									0	0
Storage and transportation									10.5	7
NGL and crude services									1,218.30	699.6
Related party (Note 16)									13.6	7.2
Cost of product/services sold									1,242.40	713.8
Expenses:
Operations and maintenance									64.3	31.3
General and administrative									6.3	10
Depreciation, amortization and accretion									44.7	26
Costs and Expenses									115.3	67.3
(Gain) loss on long-lived assets, net									31.7	-0.1
Goodwill impairment									0	0
Loss on contingent consideration									0	0
Operating income									54.4	-5.9
Other income (expense):
Earnings (loss) from unconsolidated affiliates, net									0	0
Interest and debt expense, net									0	0
Other income, net									0.6	0.2
Loss from unconsolidated affiliates									0	0
Income (loss) before income taxes									55	-5.7
Provision for income taxes									0	0.1
Net income (loss)									55	-5.8
Net income attributable to non-controlling partners in subsidiary									0	0
Net income attributable to Crestwood Equity Partners LP									55	-5.8
Non-Guarantor Subsidiaries
Revenues:
Gathering and processing									328.5	216.3
Storage and transportation									179.1	90.1
NGL and crude services									2,040.30	270.1
Related party (Note 16)									17.6	82.1
Total revenue									2,565.50	658.6
Costs of product/services sold:
Gathering and processing									29.1	24.1
Storage and transportation									14.3	8.7
NGL and crude services									1,851.90	230.4
Related party (Note 16)									42.2	32.5
Cost of product/services sold									1,937.50	295.7
Expenses:
Operations and maintenance									139	73.3
General and administrative									85.4	83.5
Depreciation, amortization and accretion									240.6	141.9
Costs and Expenses									465	298.7
(Gain) loss on long-lived assets, net									-33.6	5.4
Goodwill impairment									-48.8	-4.1
Loss on contingent consideration									-8.6	-31.4
Operating income									72	34.1
Other income (expense):
Earnings (loss) from unconsolidated affiliates, net									-0.7	-0.1
Interest and debt expense, net									-111.4	-71.4
Other income, net									0	0
Loss from unconsolidated affiliates									0	0
Income (loss) before income taxes									-40.1	-37.4
Provision for income taxes									0.7	0.7
Net income (loss)									-40.8	-38.1
Net income attributable to non-controlling partners in subsidiary									66.8	57.3
Net income attributable to Crestwood Equity Partners LP									26	19.2
Consolidation, Eliminations
Revenues:
Gathering and processing									0	0
Storage and transportation									0	0
NGL and crude services									0	0
Related party (Note 16)									-14.6	-7.2
Total revenue									-14.6	-7.2
Costs of product/services sold:
Gathering and processing									0	0
Storage and transportation									0	0
NGL and crude services									-1	0
Related party (Note 16)									-13.6	-7.2
Cost of product/services sold									-14.6	-7.2
Expenses:
Operations and maintenance									0	0
General and administrative									0	0
Depreciation, amortization and accretion									0	0
Costs and Expenses									0	0
(Gain) loss on long-lived assets, net									0	0
Goodwill impairment									0	0
Loss on contingent consideration									0	0
Operating income									0	0
Other income (expense):
Earnings (loss) from unconsolidated affiliates, net									0	0
Interest and debt expense, net									0	0
Other income, net									0	0
Loss from unconsolidated affiliates									-14.2	43.9
Income (loss) before income taxes									-14.2	43.9
Provision for income taxes									0	0
Net income (loss)									-14.2	43.9
Net income attributable to non-controlling partners in subsidiary									0	0
Net income attributable to Crestwood Equity Partners LP									-14.2	43.9
Consolidated Entities
Revenues:
Gathering and processing									328.5	216.3
Storage and transportation									192.9	104.2
NGL and crude services									3,406.90	1,031.30
Related party (Note 16)									3	74.9
Total revenue									3,931.30	1,426.70
Costs of product/services sold:
Gathering and processing									29.1	24.1
Storage and transportation									24.8	15.7
NGL and crude services									3,069.20	930
Related party (Note 16)									42.2	32.5
Cost of product/services sold									3,165.30	1,002.30
Expenses:
Operations and maintenance									203.3	104.6
General and administrative									100.2	93.5
Depreciation, amortization and accretion									285.3	167.9
Costs and Expenses									588.8	366
(Gain) loss on long-lived assets, net									-1.9	5.3
Goodwill impairment									-48.8	-4.1
Loss on contingent consideration									-8.6	-31.4
Operating income									117.9	28.2
Other income (expense):
Earnings (loss) from unconsolidated affiliates, net									-0.7	-0.1
Interest and debt expense, net									-127.1	-77.9
Other income, net									0.6	0.2
Loss from unconsolidated affiliates									0	0
Income (loss) before income taxes									-9.3	-49.6
Provision for income taxes									1.1	1
Net income (loss)									-10.4	-50.6
Net income attributable to non-controlling partners in subsidiary									66.8	57.3
Net income attributable to Crestwood Equity Partners LP									$56.40	$6.70

Condensed_Consolidating_Financ5

Condensed Consolidating Financial Information (Statements of Comprehensive Income) (Details) (USD $)	3 Months Ended								12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Condensed Financial Statements, Captions [Line Items]
Net income (loss)	($30.70)	$11.90	($4.80)	$13.20	($42.10)	($7.90)	($4.50)	$3.90	($10.40)	($50.60)	$24.40
Change in fair value of Suburban Propane Partners, L.P. units (Note 12)									-0.5	-0.1	0
Comprehensive income (loss)									-10.9	-50.7	24.4
Parent Company
Condensed Financial Statements, Captions [Line Items]
Net income (loss)									-10.4	-50.6	24.4
Change in fair value of Suburban Propane Partners, L.P. units (Note 12)									-0.5	-0.1	0
Comprehensive income (loss)									-10.9	-50.7	24.4
Guarantor Subsidiaries
Condensed Financial Statements, Captions [Line Items]
Net income (loss)									55	-5.8
Change in fair value of Suburban Propane Partners, L.P. units (Note 12)									0	0
Comprehensive income (loss)									55	-5.8
Non-Guarantor Subsidiaries
Condensed Financial Statements, Captions [Line Items]
Net income (loss)									-40.8	-38.1
Change in fair value of Suburban Propane Partners, L.P. units (Note 12)									0	0
Comprehensive income (loss)									-40.8	-38.1
Consolidation, Eliminations
Condensed Financial Statements, Captions [Line Items]
Net income (loss)									-14.2	43.9
Change in fair value of Suburban Propane Partners, L.P. units (Note 12)									0	0
Comprehensive income (loss)									-14.2	43.9
Consolidated Entities
Condensed Financial Statements, Captions [Line Items]
Net income (loss)									-10.4	-50.6
Change in fair value of Suburban Propane Partners, L.P. units (Note 12)									-0.5	-0.1
Comprehensive income (loss)									($10.90)	($50.70)

Condensed_Consolidating_Financ6

Condensed Consolidating Financial Information (Statements Of Cash Flows) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Cash flows from operating activities	$283	$188.30	$102.10
Cash flows from investing activities:
Acquisitions, net of cash acquired	-19.5	-555.6	-564
Purchases of property, plant and equipment	-424	-347	-52.6
Investment in unconsolidated affiliates	-108.6	-151.5	0
Proceeds from sale of assets	2.7	11.2	0
Proceeds from sale of Tres Palacios	66.4	0	0
Net cash used in investing activities	-483	-1,042.90	-616.6
Cash flows from financing activities:
Proceeds from the issuance of long-term debt	2,823.90	2,466.90	706.7
Principal payments on long-term debt	-2,696	-1,967.60	-534
Payments on capital leases	-3.2	-4.3	-3
Payments for debt-related deferred costs	-1.9	-33.1	-11.4
Distributions to partners	-102.5	-68.4	-13.8
Distributions paid to non-controlling partners	-296.5	-204.5	-89.7
Net proceeds from the issuance of common units	0	714	217.5
Proceeds from issuance of preferred equity of subsidiary, net	53.9	96.1	0
Net proceeds from the issuance of Crestwood Midstream Partners LP Class A preferred units	430.5
Taxes paid for unit-based compensation vesting	-3.9	-10.5	-0.4
Change in intercompany balances		0
Other	-0.7	0.1	0
Net cash provided by financing activities	203.6	859.7	513.8
Net change in cash	3.6	5.1	-0.7
Cash at beginning of period	5.2	0.1	0.8
Cash at end of period	8.8	5.2	0.1
Parent Company
Cash flows from operating activities	-25.3	-12.3	0
Cash flows from investing activities:
Acquisitions, net of cash acquired	0	0
Purchases of property, plant and equipment	-3.8	0
Investment in unconsolidated affiliates	35.8	0
Proceeds from sale of assets	0
Proceeds from sale of Tres Palacios	66.4
Capital contributions from consolidated affiliates, net	72.4
Capital contributions from consolidated affiliates, net and other		20.7
Net cash used in investing activities	170.8	20.7	-146.2
Cash flows from financing activities:
Proceeds from the issuance of long-term debt	734	394.1	0
Principal payments on long-term debt	-746.2	-333.3	0
Payments on capital leases	0
Payments for debt-related deferred costs	-1.8	0	0
Distributions to partners	-102.5	-68.4	-103.5
Distributions paid to non-controlling partners	0	0
Net proceeds from the issuance of common units		0
Proceeds from issuance of preferred equity of subsidiary, net	0	0
Net proceeds from the issuance of Crestwood Midstream Partners LP Class A preferred units	0
Taxes paid for unit-based compensation vesting	0
Change in intercompany balances	-25.4	0.4	0
Other	0	-1.1	0
Net cash provided by financing activities	-141.9	-8.3	146.2
Net change in cash	3.6	0.1	0
Cash at beginning of period	0.1	0	0
Cash at end of period	3.7	0.1	0
Guarantor Subsidiaries
Cash flows from operating activities	-14.6	14.1
Cash flows from investing activities:
Acquisitions, net of cash acquired	0	5.9
Purchases of property, plant and equipment	-13.2	-12.4
Investment in unconsolidated affiliates	0	0
Proceeds from sale of assets	2.7
Proceeds from sale of Tres Palacios	0
Capital contributions from consolidated affiliates, net	0
Capital contributions from consolidated affiliates, net and other		0.1
Net cash used in investing activities	-10.5	-6.4
Cash flows from financing activities:
Proceeds from the issuance of long-term debt	0	0
Principal payments on long-term debt	0	0
Payments on capital leases	0
Payments for debt-related deferred costs	0
Distributions to partners	0	0
Distributions paid to non-controlling partners	0	0
Net proceeds from the issuance of common units		0
Proceeds from issuance of preferred equity of subsidiary, net	0	0
Net proceeds from the issuance of Crestwood Midstream Partners LP Class A preferred units	0
Taxes paid for unit-based compensation vesting	-2.3
Change in intercompany balances	25.4	-0.4
Other	0.1	-4.9
Net cash provided by financing activities	23.2	-5.3
Net change in cash	-1.9	2.4
Cash at beginning of period	2.4	0
Cash at end of period	0.5	2.4
Non-Guarantor Subsidiaries
Cash flows from operating activities	322.9	186.5
Cash flows from investing activities:
Acquisitions, net of cash acquired	-19.5	-561.5
Purchases of property, plant and equipment	-407	-334.6
Investment in unconsolidated affiliates	-144.4	-151.5
Proceeds from sale of assets	0
Proceeds from sale of Tres Palacios	0
Capital contributions from consolidated affiliates, net	0
Capital contributions from consolidated affiliates, net and other		11.1
Net cash used in investing activities	-570.9	-1,036.50
Cash flows from financing activities:
Proceeds from the issuance of long-term debt	2,089.90	2,072.80
Principal payments on long-term debt	-1,949.80	-1,634.30
Payments on capital leases	-3.2
Payments for debt-related deferred costs	-0.1
Distributions to partners	-72.4	-155.2
Distributions paid to non-controlling partners	-296.5	-204.5
Net proceeds from the issuance of common units		714
Proceeds from issuance of preferred equity of subsidiary, net	53.9	96.1
Net proceeds from the issuance of Crestwood Midstream Partners LP Class A preferred units	430.5
Taxes paid for unit-based compensation vesting	-1.6
Change in intercompany balances	0	0
Other	-0.8	-36.3
Net cash provided by financing activities	249.9	852.6
Net change in cash	1.9	2.6
Cash at beginning of period	2.7	0.1
Cash at end of period	4.6	2.7
Consolidation, Eliminations
Cash flows from operating activities	0	0
Cash flows from investing activities:
Acquisitions, net of cash acquired	0	0
Purchases of property, plant and equipment	0	0
Investment in unconsolidated affiliates	0	0
Proceeds from sale of assets	0
Proceeds from sale of Tres Palacios	0
Capital contributions from consolidated affiliates, net	-72.4
Capital contributions from consolidated affiliates, net and other		-20.7
Net cash used in investing activities	-72.4	-20.7
Cash flows from financing activities:
Proceeds from the issuance of long-term debt	0	0
Principal payments on long-term debt	0	0
Payments on capital leases	0
Payments for debt-related deferred costs	0
Distributions to partners	72.4	26.2
Distributions paid to non-controlling partners	0	0
Net proceeds from the issuance of common units		0
Proceeds from issuance of preferred equity of subsidiary, net	0	0
Net proceeds from the issuance of Crestwood Midstream Partners LP Class A preferred units	0
Taxes paid for unit-based compensation vesting	0
Change in intercompany balances	0	0
Other	0	-5.5
Net cash provided by financing activities	72.4	20.7
Net change in cash	0	0
Cash at beginning of period	0	0
Cash at end of period	0	0
Consolidated Entities
Cash flows from operating activities	283	188.3
Cash flows from investing activities:
Acquisitions, net of cash acquired	-19.5	-555.6
Purchases of property, plant and equipment	-424	-347
Investment in unconsolidated affiliates	-108.6	-151.5
Proceeds from sale of assets	2.7
Proceeds from sale of Tres Palacios	66.4
Capital contributions from consolidated affiliates, net	0
Capital contributions from consolidated affiliates, net and other		11.2
Net cash used in investing activities	-483	-1,042.90
Cash flows from financing activities:
Proceeds from the issuance of long-term debt	2,823.90	2,466.90
Principal payments on long-term debt	-2,696	-1,967.60
Payments on capital leases	-3.2
Payments for debt-related deferred costs	-1.9
Distributions to partners	-102.5	-197.4
Distributions paid to non-controlling partners	-296.5	-204.5
Net proceeds from the issuance of common units		714
Proceeds from issuance of preferred equity of subsidiary, net	53.9	96.1
Net proceeds from the issuance of Crestwood Midstream Partners LP Class A preferred units	430.5
Taxes paid for unit-based compensation vesting	-3.9
Change in intercompany balances	0
Other	-0.7	-47.8
Net cash provided by financing activities	203.6	859.7
Net change in cash	3.6	5.1
Cash at beginning of period	5.2	0.1
Cash at end of period	$8.80	$5.20

Quarterly_Financial_Data_Unaud2

Quarterly Financial Data (Unaudited) (Details) (USD $)	3 Months Ended								12 Months Ended
In Millions, except Per Share data, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Goodwill impairment									$48.80	$4.10	$0
Revenues	997.2	1,036.20	926.3	971.6	808.2	427.2	118.9	72.4	3,931.30	1,426.70	239.5
Operating income	-0.2	43	29.4	45.7	-11.1	15.8	7.8	15.7	117.9	28.2	61.4
Earnings (loss) from unconsolidated affiliates, net	0.6	0.3	-1.5	-0.1	0.3	-0.4	0	0	-0.7	-0.1	0
Net income (loss)	-30.7	11.9	-4.8	13.2	-42.1	-7.9	-4.5	3.9	-10.4	-50.6	24.4
Net income attributable to partners	38.4	2.8	-4.4	19.6	8.3	-8.3	1.6	5.1	56.4	6.7	14.9
Basic (dollars per unit)	$0.21	$0.02	($0.02)	$0.11	$0.04	($0.05)	$0.03	$0.13	$0.30	$0.06	$0.38
Diluted (dollars per unit)	$0.21	$0.02	($0.02)	$0.11	$0.04	($0.05)	$0.03	$0.13	$0.30	$0.06	$0.38
Impaired assets to be disposed of									13.2
Impairment of intangible assets									21.3
Antero
Contingent consideration					-31.4					-31.4
Tres Palacios Holdings LLC
Earnings (loss) from unconsolidated affiliates, net									0.1
Significant Acquisitions and Disposals, Gain (Loss) on Sale or Disposal, Net of Tax	$30.60								$30.60

Schedule_I_Crestwood_Equity_Pa1

Schedule I - Crestwood Equity Partners LP - Parent Only - Balance Sheet (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jun. 30, 2012	Dec. 31, 2011
In Millions, unless otherwise specified
Condensed Financial Statements, Captions [Line Items]
Cash	$8.80	$5.20	$0.10		$0.80
Total current assets	538.1	522
Property, plant and equipment, net	3,893.80	3,905.30
Total assets	8,461.40	8,523.20	2,301.60
Accrued expenses	52.5	40.3
Current portion of long-term debt	3.7	5.1
Long-term debt, less current portion (Note 7)	2,392.80	2,260.90
Other long-term liabilities	47.2	140.4
Total partners’ capital	5,584.50	5,508.60	1,550.70		1,120
Total liabilities and partners’ capital	8,461.40	8,523.20
Parent Company
Condensed Financial Statements, Captions [Line Items]
Cash	3.7	0.1	0	0.1	0
Accounts receivable - intercompany	3.2	0		0
Total current assets	6.9	0.1		0.1
Property, plant and equipment, net	2.5	0		0
Intangible assets	1.7	0		0
Investment in consolidated affiliates	5,971.20	5,927.10		5,927.10
Total assets	5,982.30	5,927.20		5,927.20
Accrued expenses	1.9			2
Current portion of long-term debt	3			2.2
Total current liabilities	4.9	4.2		4.2
Long-term debt, less current portion (Note 7)	380	393		393
Other long-term liabilities	12.9	21.4		21.4
Total partners’ capital	5,584.50	5,508.60		5,508.60
Total liabilities and partners’ capital	$5,982.30	$5,927.20		$5,927.20

Schedule_I_Crestwood_Equity_Pa2

Schedule I - Crestwood Equity Partners LP - Parent Only - Statement of Operations (Details) (USD $)	3 Months Ended								12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Condensed Financial Statements, Captions [Line Items]
Revenues	$997.20	$1,036.20	$926.30	$971.60	$808.20	$427.20	$118.90	$72.40	$3,931.30	$1,426.70	$239.50
Loss on contingent consideration									-8.6	-31.4	6.8
Operating income	-0.2	43	29.4	45.7	-11.1	15.8	7.8	15.7	117.9	28.2	61.4
Interest and debt expense, net									-127.1	-77.9	-35.8
Income (loss) before income taxes									-9.3	-49.6	25.6
Provision for income taxes									1.1	1	1.2
Net income (loss)	-30.7	11.9	-4.8	13.2	-42.1	-7.9	-4.5	3.9	-10.4	-50.6	24.4
Net income attributable to non-controlling partners in subsidiary									66.8	57.3	-9.5
Net income attributable to Crestwood Equity Partners LP	38.4	2.8	-4.4	19.6	8.3	-8.3	1.6	5.1	56.4	6.7	14.9
Parent Company
Condensed Financial Statements, Captions [Line Items]
Revenues									0	0	0
Costs and Expenses									8.5	0	21.3
Loss on contingent consideration									0	0	6.8
Operating income									-8.5	0	-14.5
Interest and debt expense, net									-15.7	-6.5	0
Loss from unconsolidated affiliates									14.2	-43.9	38.9
Income (loss) before income taxes									-10	-50.4	24.4
Provision for income taxes									0.4	0.2	0
Net income (loss)									-10.4	-50.6	24.4
Net income attributable to non-controlling partners in subsidiary									0	0	-9.5
Net income attributable to Crestwood Equity Partners LP									($10.40)	($50.60)	$14.90

Schedule_I_Crestwood_Equity_Pa3

Schedule I - Crestwood Equity Partners LP - Parent Only - Statement of Comprehensive Income (Details) (USD $)	3 Months Ended								12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Condensed Financial Statements, Captions [Line Items]
Net income (loss)	($30.70)	$11.90	($4.80)	$13.20	($42.10)	($7.90)	($4.50)	$3.90	($10.40)	($50.60)	$24.40
Change in fair value of Suburban Propane Partners, L.P. units (Note 12)									-0.5	-0.1	0
Comprehensive income (loss)									-10.9	-50.7	24.4
Parent Company
Condensed Financial Statements, Captions [Line Items]
Net income (loss)									-10.4	-50.6	24.4
Change in fair value of Suburban Propane Partners, L.P. units (Note 12)									-0.5	-0.1	0
Comprehensive income (loss)									($10.90)	($50.70)	$24.40

Schedule_I_Crestwood_Equity_Pa4

Schedule I - Crestwood Equity Partners LP - Parent Only - Condensed Statement of Cash Flows (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Condensed Financial Statements, Captions [Line Items]
Cash Dividends Paid to Parent Company by Consolidated Subsidiaries	$72.40	$26.20	$25.80
Cash flows from operating activities	283	188.3	102.1
Cash flows from investing activities	-483	-1,042.90	-616.6
Proceeds from the issuance of long-term debt	2,823.90	2,466.90	706.7
Principal payments on long-term debt	-2,696	-1,967.60	-534
Payments for debt-related deferred costs	-1.9	-33.1	-11.4
Distributions to partners	-102.5	-68.4	-13.8
Contributions received	0	0	-249.7
Change in intercompany balances		0
Other	-0.7	0.1	0
Net cash provided by financing activities	203.6	859.7	513.8
Net change in cash	3.6	5.1	-0.7
Cash at beginning of period	5.2	0.1	0.8
Cash at end of period	8.8	5.2	0.1
Parent Company
Condensed Financial Statements, Captions [Line Items]
Cash flows from operating activities	-25.3	-12.3	0
Cash flows from investing activities	170.8	20.7	-146.2
Proceeds from the issuance of long-term debt	734	394.1	0
Principal payments on long-term debt	-746.2	-333.3	0
Payments for debt-related deferred costs	-1.8	0	0
Distributions to partners	-102.5	-68.4	-103.5
Contributions received	0	0	249.7
Change in intercompany balances	-25.4	0.4	0
Other	0	-1.1	0
Net cash provided by financing activities	-141.9	-8.3	146.2
Net change in cash	3.6	0.1	0
Cash at beginning of period	0.1	0	0
Cash at end of period	3.7	0.1	0
As Previously Reported | Parent Company
Condensed Financial Statements, Captions [Line Items]
Cash flows from operating activities		0
Cash flows from investing activities		76
Proceeds from the issuance of long-term debt		0
Principal payments on long-term debt		0
Distributions to partners		-76
Change in intercompany balances		0
Other		0.1
Net cash provided by financing activities		($75.90)

Schedule_II_Crestwood_Equity_P1

Schedule II - Crestwood Equity Parnters LP - Valuation and Qualifying Accounts (Details) (Allowance for Doubtful Accounts [Member], USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Allowance for Doubtful Accounts [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Valuation Allowances and Reserves, Balance	$0.10	$0
Valuation Allowances and Reserves, Charged to Cost and Expense	0	-1.1
Valuation Allowances and Reserves, Charged to Other Accounts	0	1.2
Valuation Allowances and Reserves, Deductions	0	0
Valuation Allowances and Reserves, Balance	$0.10	$0.10