Net Income (Loss) Per Share (Details 1) (USD $) In Thousands, except Per Share data	3 Months Ended	9 Months Ended
Sep. 30, 2011	Oct. 01, 2010	Sep. 30, 2011	Oct. 01, 2010
Numerators and denominators of the basic and diluted net income (loss) per share computations
Net income (loss) (numerator)	$ 3,546	$ (361)	$ 4,452	$ 9,403
Shares calculation (denominator):
Weighted average shares outstanding- basic	115,791	100,246	114,855	97,975
Effect of dilutive securities:
Potential common stock relating to stock options, restricted stock units and ESPP	417		1,150	697
Weighted average shares outstanding-diluted	116,208	100,246	116,005	98,672
Net income per share-basic	$ 0.03	$ 0.00	$ 0.04	$ 0.10
Net income per share-diluted	$ 0.03	$ 0.00	$ 0.04	$ 0.10

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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+ Details

- Definition

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.

+ References+ Details

- Definition

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

+ References

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-Appendix A

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-Glossary Other Comprehensive Income

-URI http://asc.fasb.org/extlink&oid=6519514

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-Publisher FASB

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-Glossary Net Income

-URI http://asc.fasb.org/extlink&oid=6518256

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-Number 210

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+ Details

- Definition

The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

+ References+ Details

- Definition

Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

+ References

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-Publisher FASB

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-Glossary Weighted-Average Number of Common Shares Outstanding

-URI http://asc.fasb.org/extlink&oid=6528421

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+ Details