Share-Based Compensation (Narrative) (Details) - $ / shares	3 Months Ended
Dec. 31, 2020	Jan. 28, 2021
Market-Based Deferred Stock Unit
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of units/shares granted	76,747
Performance period	3 years
Weighted average grant date fair value (in dollars per unit/share)	$ 235.48
Time-Based Deferred Stock Unit
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of units/shares granted	99,246
Weighted average grant date fair value (in dollars per unit/share)	$ 280.51
LTIP \| Subsequent event
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized for future grants		1,500,000

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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