Note 8 - Shareholders' Equity (Details Textual) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended
Jan. 31, 2018	Apr. 01, 2018	Apr. 02, 2017
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Stock Options		$ 309
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition		1 year
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value		$ 3.19
Excess Tax Benefit from Share-based Compensation, Financing Activities		$ 0	$ 0
Proceeds from Stock Options Exercised		$ 939	$ 741
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value		$ 7.16
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options		$ 110
Restricted Stock [Member] \| The 2014 Long-term Incentive Plan [Member]
Stock Issued During Period, Shares, Restricted Stock Award, Gross	17,500
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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Unrecognized cost of unvested options awarded to employees as compensation.

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Amount of cash inflow from realized tax benefit related to deductible compensation cost reported on the entity's tax return for equity instruments in excess of the compensation cost for those instruments recognized for financial reporting purposes.

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Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards.

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