Discontinued Operations (Details) (USD $)	3 Months Ended	6 Months Ended
Jul. 03, 2011	Jul. 04, 2010	Jul. 03, 2011	Jul. 04, 2010	May 06, 2011
(Loss)/income from discontinued operations for the external storage systems business
Revenues	$ 51,675,000	$ 165,958,000	$ 207,365,000	$ 330,468,000
(Loss)/income before income taxes	(14,590,000)	6,939,000	(22,500,000)	19,413,000
Gain on sale of external storage systems business	260,066,000		260,066,000
(Benefit from)/provision for income taxes	(19,900,000)	2,189,000	(19,418,000)	6,491,000
Income from discontinued operations	265,376,000	4,750,000	256,984,000	12,922,000
Discontinued Operations (Textuals) [Abstract]
Transitional services as part of asset purchase agreement			up to eighteen months
Agreed sale price for external storage system					480,000,000
Write down of assets	9,500,000		20,400,000
Released deferred tax liabilities related to sale of external storage systems business	$ 19,700,000		$ 19,700,000

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Discontinued Operations.

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Gain loss on sale of business.

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Transitional services as part of asset purchase agreement.

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The cumulative amount of the estimated future tax effects attributable to the difference between the tax basis of tax-deductible goodwill and the basis of goodwill computed in accordance with generally accepted accounting principles. The difference in basis will increase future taxable income when such difference reverses.

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Overall income (loss) from a disposal group that is classified as a component of the entity, before income tax, reported as a separate component of income before extraordinary items. Includes the following (before income tax): income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal.

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Amount of sales or other form of revenues attributable to the disposal group, including a component of the entity (discontinued operation), during the reporting period.

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