Minimum period the individual is required to perform services to be fully vested under the deferred compensation arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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-Name Accounting Standards Codification

-Topic 710

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

-Glossary Accumulated Benefit Obligation

-URI http://asc.fasb.org/extlink&oid=6503844

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The interest rate used to adjust for the time value of money for the plan.

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Expected rate of compensation increases (for pay-related plans).

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The increase in the fair value of plan assets from contributions made by the employer.

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Target allocation of investments of this type to total plan assets presented on a weighted average basis.

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Amount of employer's best estimate of contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position.

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Percentage employer matches of the employee's percentage contribution matched.

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Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan.

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Total retirement, post-retirement benefit plan and defined benefit plan expense for the fiscal year.

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Retirement Plans - Additional Information (Detail) $ in Millions	12 Months Ended
	Oct. 02, 2015 USD ($) plan	Sep. 26, 2014 USD ($)	Sep. 27, 2013 USD ($)
Retirement Plans [Line Items]
Total retirement, post-retirement benefit plan and defined benefit plan expense \| $	$ 32.1	$ 28.6	$ 29.0
Accumulated benefit obligation for defined benefit pension plans \| $	$ 175.6	$ 172.7
Equity Securities
Retirement Plans [Line Items]
Target percentage allocation	30.40%
Debt and fixed income assets
Retirement Plans [Line Items]
Target percentage allocation	59.50%
Other
Retirement Plans [Line Items]
Target percentage allocation	10.10%
Foreign Postretirement Benefit Plan
Retirement Plans [Line Items]
Number of immaterial plans	2
Defined Benefit Plans
Retirement Plans [Line Items]
Discount rate (as a percent)	2.09%	2.77%
Rate of projected compensation increase (as a percent)	2.50%	2.45%
Contributions by employer \| $	$ 6.9	$ 7.2
Expected total contribution to the defined benefit plans for the fiscal year 2015 \| $	$ 7.6
Defined Benefit Plans \| Minimum
Retirement Plans [Line Items]
Discount rate (as a percent)	1.10%
Rate of projected compensation increase (as a percent)	1.75%
Defined Benefit Plans \| Maximum
Retirement Plans [Line Items]
Discount rate (as a percent)	3.90%
Rate of projected compensation increase (as a percent)	3.60%
U.K. Savings Plan
Retirement Plans [Line Items]
Number of plans	7
United States Retirement Plan \| Minimum
Retirement Plans [Line Items]
Participant contribution for eligible base compensation (as a percent)	1.00%
United States Retirement Plan \| Maximum
Retirement Plans [Line Items]
Participant contribution for eligible base compensation (as a percent)	25.00%
Contribution as percentage on after-tax basis (as a percent)	15.00%
US 401(K) Plan
Retirement Plans [Line Items]
Maximum eligible participant compensation that company matches under defined contribution plan (as a percent)	6.00%
Years of service	1 year
U.K. Savings Plan
Retirement Plans [Line Items]
Maximum eligible participant compensation that company matches under defined contribution plan (as a percent)	6.00%
U.K. Savings Plan \| Minimum
Retirement Plans [Line Items]
Participant contribution for eligible base compensation (as a percent)	4.00%
U.K. Savings Plan \| Maximum
Retirement Plans [Line Items]
Participant contribution for eligible base compensation (as a percent)	100.00%
GERMANY \| U.K. Savings Plan
Retirement Plans [Line Items]
Number of immaterial plans	1
PHILIPPINES \| U.K. Savings Plan
Retirement Plans [Line Items]
Number of immaterial plans	1