v3.10.0.1

Partners' Capital and Distributions (Changes In Limited Partner Units Outstanding) (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Capital Unit [Line Items]
Amount Authorized Under Equity Distribution Agreement		$ 750.0
Limited Partners' Capital Account [Roll Forward]
Limited partner unitholders, units outstanding (in shares)		228,024,556	227,783,916	227,427,247
Partners' Capital Account, Units, Unit-based Compensation (in shares)		168,913	216,679	350,552
Limited partner unitholders, units outstanding (in shares)		228,195,160	228,024,556	227,783,916
Limited Partners' Capital Account, Right to Receive Distribution in Cash, Period		45 days
Limited Partners' Capital Account, Removal of Magellan GP, LLC, Percentage Vote		100.00%
Limited Partners' Capital Account, Annual Report Available, Period		120 days
Limited Partners' Capital Account, Tax Reporting Information, Period		90 days
Management [Member]
Limited Partners' Capital Account [Roll Forward]
Partners' Capital Account, Units, Unit-based Compensation (in shares)		168,913	216,679	350,552
Director [Member]
Limited Partners' Capital Account [Roll Forward]
Partners' Capital Account, Units, Unit-based Compensation (in shares)	[1]	1,691	23,961	6,117
[1] Limited partner units issued to settle the equity-based retainer paid to independent directors of our general partner.

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Limited Partners' Capital Account, Removal of Magellan GP, LLC, Percentage Vote

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Limited Partners' Capital Account, Right to Receive Distribution in Cash, Period

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The number of limited partner units outstanding.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 5
-Subparagraph (SAB Topic 4.F)
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