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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