Employee Retirement Plans (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Sep. 29, 2012 year item	Sep. 24, 2011	Sep. 25, 2010
Employee Retirement Plans
Minimum hours per week to be eligible for participation in the plan	36
Minimum age of eligible employees	18
Percentage match of employee contributions	50.00%
Percent of maximum annual contribution per employee	6.00%
Contributions to 401(k) plan	$ 4.4	$ 2.7	$ 2.0
Canadian Plans
Contributions to Canadian plans	1.0	0.8
Defined Benefit Plan
Projected benefit obligation	1.1	2.3
Projected benefit obligation included in accrued liabilities		0.1
Projected benefit obligation classified in other long-term liabilities		1.5
Projected benefit obligation classified in current liabilities related to assets held for sale		0.7
Net periodic pension (income) expense	$ (0.1)	$ 0.5

Represents the minimum age required for an employee to be eligible to participate in the defined contribution plan.

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- Definition

Represents the minimum hours per week and employee must work to participate in the defined contribution plan.

+ References

No definition available.

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- Definition

For a classified balance sheet, the amount recognized in balance sheet as a current liability associated with an underfunded defined benefit plan and related to assets held for sale.

+ References

No definition available.

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- Definition

The amount of payment into the fund established for purposes of making future disbursements to the individual in accordance with the terms and understanding of the deferred compensation arrangement.

+ References

No definition available.

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- Definition

1) For defined benefit pension plans, the benefit obligation is the projected benefit obligation, which is the actuarial present value as of a date of all benefits attributed by the pension benefit formula to employee service rendered prior to that date. 2) For other postretirement defined benefit plans, the benefit obligation is the accumulated postretirement benefit obligation, which is the actuarial present value of benefits attributed to employee service rendered to a particular date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Accumulated Postretirement Benefit Obligation

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-Glossary Projected Benefit Obligation

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- Definition

The total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments.

+ References

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- Definition

The amount of the cost recognized during the period for defined contribution plans.

+ References

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- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

+ References

No definition available.

+ Details

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- Definition

Maximum percentage of employee gross pay, by the terms of the plan, that the employer may contribute to a defined contribution plan.

+ References

No definition available.

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- Definition

For a classified balance sheet, the amount recognized in balance sheet as a current liability associated with an underfunded defined benefit plan.

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-Glossary Current Liabilities

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- Definition

This represents the noncurrent liability for underfunded plans recognized in the balance sheet that is associated with the defined benefit pension plans and other postretirement defined benefit plans.

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