Stock-Based Compensation (Narrative) (Details) - $ / shares	9 Months Ended
Jun. 30, 2018	Jul. 01, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted (in shares)	245,000	288,000
Weighted average grant date fair value (in dollars per share)	$ 11.10	$ 8.91
Restricted stock units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value (in dollars per share)	49.63	45.00
Performance restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value (in dollars per share)	$ 49.63	$ 45.00
2017 Stock incentive plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for grant (in shares)	1,258,000
2012 Employee stock purchase plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for grant (in shares)	615,000
Stock issued during period (in shares)	24,000	25,000
Weighted average price of shares issued (in dollars per share)	$ 44.39	$ 40.49
Directors, Officers and Employees \| Restricted stock units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted issued (in shares)	109,000	118,000
Directors, Officers and Employees \| Performance restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted issued (in shares)	29,000	35,000

Employee Stock Purchase Plan Per Share Weighted Average Price of Shares Issued

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

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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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Number of shares issued during the period as a result of an employee stock purchase plan.

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