Partners' Capital (Schedule of Partners' Capital Account, Distributions) (Details) - USD ($) $ / shares in Units, $ in Millions									6 Months Ended
May 13, 2022	May 06, 2022	Feb. 14, 2022	Feb. 07, 2022	May 14, 2021	May 07, 2021	Feb. 12, 2021	Feb. 05, 2021	Jun. 30, 2022	Jun. 30, 2021
Distribution Made to Limited Partner [Line Items]
Distribution Made to Limited Partner, Date of Record		May 06, 2022		Feb. 07, 2022		May 07, 2021		Feb. 05, 2021
Distribution Made to Limited Partner, Distribution Date	May 13, 2022		Feb. 14, 2022		May 14, 2021		Feb. 12, 2021
Distribution Made to Member or Limited Partner, Distributions Paid, Per Unit	$ 0.655		$ 0.625		$ 0.625		$ 0.625
Distribution Made to Limited Partner, Cash Distributions Paid	$ 64.2		$ 60.9		$ 39.3		$ 46.4		$ 125.1	$ 85.7

Amount of cash distribution paid to unit-holder of limited partnership (LP).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI https://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770

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Date of record for distribution of cash or unit to limited partner of limited partnership (LP), in YYYY-MM-DD format.

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Date of distribution for distribution of cash or unit to limited partner of limited partnership (LP), in YYYY-MM-DD format.

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Per unit of ownership amount of cash distributions paid to unit-holder of a limited partnership (LP).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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