Net Income per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
Apr. 01, 2017	Apr. 02, 2016
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Net income available to common stockholders, basic	$ (2,237)	$ 2,971
Weighted average number of shares outstanding, basic	36,563	34,633
Diluted (in shares)	36,563	36,546
Basic (in dollars per share)	$ (0.06)	$ 0.09
Diluted (in dollars per share)	$ (0.06)	$ 0.08
Stock Options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Incremental common shares attributable to dilutive effect of share-based payment arrangements	0	689
Restricted Stock Units (RSUs)
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Incremental common shares attributable to dilutive effect of share-based payment arrangements	0	984
Performance Units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Incremental common shares attributable to dilutive effect of share-based payment arrangements	0	14
ESPP Purchase Right
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Incremental common shares attributable to dilutive effect of share-based payment arrangements	0	226
Option Plans Awards To Purchase Common Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	148	274

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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