Net Income Per Share (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 29, 2013	Mar. 30, 2012
Basic and diluted earnings per share
Weighted-average number of shares outstanding during period	15,430	15,169
Common stock equivalents - incremental shares primarily under stock option plans	1,636	1,703
Number of shares on which diluted earnings per share is based	17,066	16,872
Net income	$ 4,057	$ 3,360
Earnings per share, basic (in dollars per share)	$ 0.26	$ 0.22
Earnings per share, diluted (in dollars per share)	$ 0.24	$ 0.20

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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-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 51

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-Appendix A

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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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-Glossary Weighted-Average Number of Common Shares Outstanding

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

+ Details