Stock-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	9 Months Ended
Jun. 26, 2021	Jun. 27, 2020
Stock option plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted (in shares)	0.6	0.9
Weighted-average exercise prices (in dollars per share)	$ 68.62	$ 45.54
Share-based compensation, stock options outstanding (in shares)	4.4
Weighted-average exercise price of options outstanding (in dollars per share)	$ 44.51
Unrecognized compensation expense	$ 19.4
Weighted-average period for recognition of unrecognized stock-based compensation, years	2 years 4 months 24 days
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares)	0.5	0.8
Restricted stock units (RSUs), weighted average grant date fair values (in dollars per share)	$ 68.45	$ 45.67
Unrecognized compensation expense	$ 61.1
Weighted-average period for recognition of unrecognized stock-based compensation, years	2 years
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares)	0.1	0.1
Restricted stock units (RSUs), weighted average grant date fair values (in dollars per share)	$ 68.51	$ 45.38
Market Based Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares)	0.1	0.1
Restricted stock units (RSUs), weighted average grant date fair values (in dollars per share)	$ 82.51	$ 43.54
Minimum eligible percentage to receive target number of shares of company's common stock	0.00%
Maximum eligible percentage to receive target number of shares of company's common stock	200.00%
Performance stock units vesting period	3 years
PSU Free Cash Flow [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares)	0.1	0.1
Restricted stock units (RSUs), weighted average grant date fair values (in dollars per share)	$ 68.51	$ 45.38
Minimum eligible percentage to receive target number of shares of company's common stock	0.00%
Maximum eligible percentage to receive target number of shares of company's common stock	200.00%
Performance stock units vesting period	3 years
RSU, PSU, MSU
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number (in shares)	3.0

Maximum target number percentage of shares issued based on stock performance.

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Minimum target number percentage of shares that would be issued based on stock price performance.

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Period of time that must lapse in order for the restricted stock units to vest.

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No definition available.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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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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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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

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Number of options outstanding, including both vested and non-vested options.

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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