Partners' Capital (Components of Net Income (Loss) Attributable to Non-Controlling Interests) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Distribution Made to Limited Partner [Line Items]
Payments of Ordinary Dividends, Noncontrolling Interest	$ 9.2	$ 3.3
Net income attributable to non-controlling partners in subsidiaries	(9.9)	(4.0)
Crestwood Midstream Partners LP
Distribution Made to Limited Partner [Line Items]
Payments of Ordinary Dividends, Noncontrolling Interest	9.2	3.3
Net income attributable to non-controlling partners in subsidiaries	(9.9)	(4.0)
Crestwood Niobrara LLC
Distribution Made to Limited Partner [Line Items]
Payments of Ordinary Dividends, Noncontrolling Interest	$ 9.2	$ 3.3

Amount of Net Income (Loss) attributable to noncontrolling interest.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 1B
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118930883&loc=SL7669625-108580

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 1A
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-URI http://asc.fasb.org/extlink&oid=109239629&loc=SL4573702-111684

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 1A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118930883&loc=SL7669619-108580

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 55
-Paragraph 4J
-URI http://asc.fasb.org/extlink&oid=116874947&loc=SL4591551-111686

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