Restructuring and Contract Termination Costs (Details) (USD $) In Thousands	9 Months Ended
Sep. 24, 2011	Sep. 25, 2010
Restructuring and Contract Termination Costs
Accrued severance and retention costs included in accrued compensation	$ 1,932
Accrued severance and retention costs included in other long-term liabilities	2,418
Severance charges included in cost of sales	437
Severance charges included in selling, general and administrative expense	880
Impairment charges	970
Severance and Retention Costs
Balance at the beginning of the period	10,658	4,332
Expense	1,317	5,571
Payments/utilization	(7,625)	(6,317)
Balance at the end of the period	$ 4,350	$ 3,586

Represents the charge against earnings from the aggregate write down of all assets from their carrying value to their value as a result of restructuring activities.

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Represents the amount of cash paid to fully or partially settle a specified, previously accrued type of restructuring cost. Also represents the utilization of the restructuring reserve during the period.

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The charge against earnings in the period for known and estimated costs of termination benefits provided to current employees that are involuntarily terminated under a benefit arrangement associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, excluding costs or losses pertaining to an entity newly acquired in a business combination or a discontinued operation as defined by generally accepted accounting principles and costs associated with one-time termination benefits, included in cost of sales.

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

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Carrying amount as of the balance sheet date of known and estimated obligations associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, which are expected to be paid in the next twelve months or in the normal operating cycle if longer. Costs of such activities include those for one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, relocating employees, and costs associated with an ongoing benefit arrangement, but excludes costs associated with the retirement of a long-lived asset.

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Carrying amount as of the balance sheet date of known and estimated costs associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, which are expected to be paid after one year or beyond the next operating cycle, if longer. Costs of such activities include those for one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, and relocating employees, and costs associated with an ongoing benefit arrangement, but excludes costs associated with the retirement of a long-lived asset.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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