Net Income Per Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
Apr. 04, 2015	Mar. 29, 2014
Earnings Per Share [Abstract]
Basic and diluted Net (loss) income	$ (53,347)us-gaap_NetIncomeLoss	$ 11,984us-gaap_NetIncomeLoss
Shares used in basic Net (loss) income per share (in shares)	116,863,000	116,436,000
Dilutive effect of stock options, RSUs and ESPP shares (in shares)	0	2,481,000
Shares used in diluted Net (loss) income per share (in shares)	116,863,000	118,917,000
Basic Net (loss) income per share (in dollars per share)	$ (0.46)us-gaap_EarningsPerShareBasic	$ 0.10us-gaap_EarningsPerShareBasic
Diluted Net (loss) income per share (in dollars per share)	$ (0.46)us-gaap_EarningsPerShareDiluted	$ 0.10us-gaap_EarningsPerShareDiluted
Stock options, RSU's and ESPP shares
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of EPS (in shares)	11,500,000	5,300,000

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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