Net Income per Share (Details) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended	9 Months Ended
Sep. 28, 2019	Sep. 29, 2018	Sep. 28, 2019	Sep. 29, 2018
Net income available to common shareholders
Net income, as reported	$ 5,739	$ 3,908	$ 15,984	$ 15,633
Less: net income attributable to participating shares	12	15	47	82
Net income available to common shareholders	$ 5,727	$ 3,893	$ 15,937	$ 15,551
Reconciliation of basic to diluted weighted average shares of common stock outstanding
Basic weighted average shares outstanding	7,769	8,048	7,903	8,129
Dilutive stock options and restricted stock units	281	500	302	486
Diluted weighted average shares outstanding	8,050	8,548	8,205	8,615
Calculation of common stock equivalents for purposes of computing diluted weighted average shares outstanding
Anti-dilutive securities excluded from EPS computation (in shares)	63,164	8,256	47,169	13,443

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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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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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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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Amount of undistributed earnings (loss) allocated to participating securities for the basic earnings (loss) per share or per unit calculation under the two-class method.

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