Earnings Per Share (Excluded from Diluted Earnings Per Share Calculation) (Details) - $ / shares shares in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Weighted-average number of shares	0.1	0.3
Price range per share (in dollars per share)	$ 278.00
Minimum [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Price range per share (in dollars per share)		$ 214.63
Maximum [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Price range per share (in dollars per share)		$ 270.83

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

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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.

+ References

No definition available.

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- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic net Income or Loss per outstanding limited partnership unit in the future and that were not included in the computation of diluted net income per limited partnership unit, because to do so would increase net income per unit amounts or decrease loss per unit amounts for the period presented.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

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