Discontinued Operations (Details) (USD $)	3 Months Ended	9 Months Ended
Oct. 02, 2011	Oct. 03, 2010	Oct. 02, 2011	Oct. 03, 2010	May 06, 2011
(Loss)/income from discontinued operations for the external storage systems business
Revenues	$ 2,860,000	$ 176,106,000	$ 210,225,000	$ 506,574,000
(Loss)/income before income taxes	(2,366,000)	16,246,000	(24,866,000)	35,659,000
Gain on sale of external storage systems business			260,066,000
(Benefit from)/provision for income taxes	(55,000)	5,644,000	(19,473,000)	12,135,000
(Loss)/Income from discontinued operations	(2,311,000)	10,602,000	254,673,000	23,524,000
Discontinued Operations (Textuals) [Abstract]
Period to provide certain 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 associated with discontinued operations	2,600,000		23,000,000
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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Discontinued operations write down of assets.

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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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Tax effect allocated to a disposal group that is classified as a component of the entity reported as a separate component of income before extraordinary items. Includes the tax effects of the following: 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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