Stock-Based Compensation Plans Stock-Based Compensation Plans (Schedule Of Future Share-Based Compensation Cost) - Equity Option [Member] - USD ($) $ / shares in Units, $ in Millions		3 Months Ended	6 Months Ended
Jul. 21, 2021	Sep. 30, 2021	Jun. 30, 2021
Share -based Compensation Arrangement by Share-based Payment Award [Line Items]
2021		$ 18.9
2022		36.9
2023		36.3
2024		36.3
2025		2.2
Total	$ 145.3	$ 130.6
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value		$ 171.36
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	770,500	8,000	770,500

Employee Service Share Based Compensation Estimated Allocation Of Recognized Period Costs In Five Years

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- Definition

Employee Service Share Based Compensation Estimated Allocation Of Recognized Period Costs In Four Years

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- Definition

Employee Service Share Based Compensation Estimated Allocation Of Recognized Period Costs In Three Years

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- Definition

Employee Service Share Based Compensation Estimated Allocation Of Recognized Period Costs In Two Years

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- Definition

Employee Service Share Based Compensation Estimated Allocation Of Recognized Period Costs Next Twelve Months

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- Definition

Employee Service Share Based Compensation Estimated Allocation Of Recognized Period Costs Total

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- Definition

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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- Definition

Gross number of share options (or share units) granted during the period.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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