Income Taxes - Valuation Allowance Against Deferred Tax Assets (Details) (USD $)	12 Months Ended
Dec. 27, 2014	Dec. 28, 2013	Dec. 29, 2012
Deferred Tax Assets Valuation Allowance [Roll Forward]
Balance at Beginning of Year	$ 180,913,000	$ 163,265,000	$ 168,875,000
Additions	6,846,000	17,648,000	19,910,000
Reduction	0	0	(25,520,000)
Balance at End of Year	187,759,000	180,913,000	163,265,000
Federal
Deferred Tax Assets Valuation Allowance [Roll Forward]
Federal research and development tax credit, carryforwards.	19,300,000
Federal foreign tax credit carryforwards.	293,900,000
Federal foreign tax credit carryforwards.	1,900,000
Alternative minimum tax credits.	2,400,000
Livermore, California
Deferred Tax Assets Valuation Allowance [Roll Forward]
Federal foreign tax credit carryforwards.	270,800,000
California research credit carryforwards.	26,500,000
Singapore
Deferred Tax Assets Valuation Allowance [Roll Forward]
Singapore net operating loss carryforwards.	$ 10,600,000

Deferred Tax Assets, Tax Credit Carryforwards, Foreign, Subject to Expiration

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Deferred Tax Assets, Tax Credit Carryforwards, Research, Subject to Expiration

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Deferred Tax Assets Valuation Allowance, Additions

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Deferred Tax Assets Valuation Allowance, Reduction

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards that are not subject to expiration dates.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards that are subject to expiration dates.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible alternative minimum tax credit carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible research tax credit carryforwards.

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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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