Earnings Per Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
Jan. 03, 2015	Dec. 28, 2013	Dec. 29, 2012
Earnings Per Share
Net income	$ 38,021	$ 49,819	$ 63,548
Shares used in computing basic earnings per share	42,970,000	42,715,000	42,136,000
Effect of dilutive securities:
Stock options and other stock-based awards (in shares)	823,000	822,000	970,000
Shares used in computing diluted earnings per share	43,793,000	43,537,000	43,106,000
Earnings per share:
Basic (in dollars per share)	$ 0.88us-gaap_EarningsPerShareBasic	$ 1.17us-gaap_EarningsPerShareBasic	$ 1.51us-gaap_EarningsPerShareBasic
Diluted (in dollars per share)	$ 0.87us-gaap_EarningsPerShareDiluted	$ 1.14us-gaap_EarningsPerShareDiluted	$ 1.47us-gaap_EarningsPerShareDiluted
Shares excluded from computation of diluted earning per share	100,000	400,000	500,000

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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