Stock-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
Dec. 28, 2019	Dec. 29, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Purchase of insurance contracts	$ 2.4	$ 0.0
Stock option plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted	0.8	0.9
Weighted-average exercise prices	$ 45.67	$ 40.96
Share-based compensation, stock option outstanding	5.7
Weighted-average exercise price of options outstanding	$ 37.66
Unrecognized compensation expense	$ 30.4
Weighted-average period for recognition of unrecognized stock-based compensation, years	2 years 9 months 18 days
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted	0.7	0.9
Restricted stock units (RSUs), weighted average grant date fair values	$ 45.64	$ 40.98
Unrecognized compensation expense	$ 85.9
Weighted-average period for recognition of unrecognized stock-based compensation, years	2 years 2 months 12 days
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted	0.1	0.1
Restricted stock units (RSUs), weighted average grant date fair values	$ 45.65	$ 40.97
Market Based Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted	0.1	0.1
Restricted stock units (RSUs), weighted average grant date fair values	$ 43.78	$ 55.13
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	0.1
Restricted stock units (RSUs), weighted average grant date fair values	$ 45.65
Maximum eligible percentage to receive target number of shares of company's common stock	200.00%
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	2.6

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.

+ References

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- Definition

Purchase of insurance contracts

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

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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- Definition

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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- Definition

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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- Definition

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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No definition available.

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- Definition

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

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- Definition

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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- Definition

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

+ References

No definition available.

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