Income Taxes (Components Of Deferred Tax Assets And Liabilities) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 27, 2014	Dec. 28, 2013
Income Taxes [Abstract]
Net operating loss carryforwards	$ 16,609	$ 30,549
Credit carryforwards	49,638	88,854
Reserves and accrued expenses	10,088	6,008
Stock-based compensation	11,643	11,688
Other	471us-gaap_DeferredTaxAssetsOther	358us-gaap_DeferredTaxAssetsOther
Capitalized technology & other	4,637	3,290
Capital loss		1,208
Depreciation and amortization	18,721	15,903
Total deferred tax assets	111,807us-gaap_DeferredTaxAssetsGross	157,858us-gaap_DeferredTaxAssetsGross
Valuation allowance	(86,948)	(92,525)
Deferred tax assets, net of valuation allowance	24,859us-gaap_DeferredTaxAssetsNet	65,333us-gaap_DeferredTaxAssetsNet
Deferred income tax on credits	(10,687)	(8,864)
Goodwill amortization	(52,001)	(44,946)
Federal benefits	(4,454)	(10,300)
Total deferred tax assets, net	$ (42,283)us-gaap_DeferredTaxAssetsLiabilitiesNet	$ 1,223us-gaap_DeferredTaxAssetsLiabilitiesNet

Deferred Tax Assets, Depreciation and Amortization

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Deferred Tax Liabilities Deferred Income Tax On Credits

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Deferred Tax Liabilities Federal Benefits

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible capital loss carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards, net of deferred tax liability attributable to taxable temporary differences.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences not separately disclosed.

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The tax effect as of the balance sheet date of the amount of future tax deductions arising from all unused tax credit carryforwards which have been reduced by a valuation allowance.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from share-based compensation.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from accrued liabilities.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Amount of deferred tax liability attributable to taxable temporary differences from research and development costs.

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Amount of deferred tax liability attributable to taxable temporary differences from goodwill.

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