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Note 12 - Shareholders' Equity (Details Textual) $ / shares in Units, $ in Thousands | 3 Months Ended | 12 Months Ended |  |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | ---
Apr. 02, 2017 USD ($) | Dec. 30, 2018 USD ($) $ / shares shares | Dec. 31, 2017 USD ($) $ / shares shares | Jan. 01, 2017 USD ($) $ / shares shares | Jul. 02, 2017 USD ($) | Jul. 03, 2016 USD ($) | Nov. 19, 2015 shares | May 31, 2015 shares | Oct. 07, 2014 shares | Mar. 05, 2012 $ / shares shares
Common Stock, Shares Authorized | shares |  |  |  |  |  |  |  |  |  | 120,000,000
Common Stock, Par or Stated Value Per Share | $ / shares |  |  |  |  |  |  |  |  |  | $ 0.10
Common Stock, Dividends, Per Share, Cash Paid | $ / shares |  | $ 0.26 | $ 0.25 | $ 0.22 |  |  |  |  |  |
Stock Repurchase Program, Remaining Authorized Repurchase Amount |  | $ 25,100 |  |  |  |  |  |  |  |
Stock Based Compensation Rate at Which Employee Stock Option Exercisable |  | 100.00% |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized | shares |  |  |  |  |  |  |  | 5,161,020 |  |
Number of Authorized Stock Reduced by Issuance of Other Than Stock Option Award |  |  |  |  |  |  |  | 1.33 |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term |  | 1 year |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term |  | 1 year |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value |  | $ 200 |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value |  | $ 200 |  |  |  |  |  |  |  |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Lower Range Limit | $ / shares |  | $ 4.31 |  |  |  |  |  |  |  |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Upper Range Limit | $ / shares |  | $ 12.43 |  |  |  |  |  |  |  |
Employee Stock Option [Member] |  |  |  |  |  |  |  |  |  |
Allocated Share-based Compensation Expense, Total |  | $ 0 | $ 0 | $ 0 |  |  |  |  |  |
Employee Stock Option [Member] | Minimum [Member] |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period |  | 1 year |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period |  | 3 years |  |  |  |  |  |  |  |
Employee Stock Option [Member] | Maximum [Member] |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period |  | 5 years |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period |  | 10 years |  |  |  |  |  |  |  |
Restricted Stock [Member] |  |  |  |  |  |  |  |  |  |
Allocated Share-based Compensation Expense, Total |  | $ 4,100 | $ 2,800 | $ 4,700 |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period | shares |  | 194,000 | 253,000 | 277,000 |  |  |  |  |  |
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options |  | $ 4,200 |  |  |  |  |  |  |  |
Restricted Stock [Member] | Minimum [Member] |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period |  | 2 years |  |  |  |  |  |  |  |
Restricted Stock [Member] | Maximum [Member] |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period |  | 5 years |  |  |  |  |  |  |  |
Performance Shares [Member] |  |  |  |  |  |  |  |  |  |
Allocated Share-based Compensation Expense, Total |  | $ 10,400 | $ 4,500 | $ 1,200 |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period | shares |  | 261,000 |  |  |  |  |  |  |  |
Share-Based Compensation Arrangement By Share-Based Payment Award, Equity Instruments Other Than Options, Shares Issued During Exercise of Instrument, Upper Limit, Percentage |  | 200.00% |  |  |  |  |  |  |  |
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Total |  | $ 4,000 |  |  |  |  |  |  |  |
Performance Shares [Member] | Minimum [Member] |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period |  | 1 year |  |  |  |  |  |  |  |
Performance Shares [Member] | Maximum [Member] |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period |  | 3 years |  |  |  |  |  |  |  |
Restricted Stock and Performance Shares [Member] |  |  |  |  |  |  |  |  |  |
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense |  | $ 2,400 | 2,600 | 2,000 |  |  |  |  |  |
Common Stock [Member] |  |  |  |  |  |  |  |  |  |
Stock Repurchase Program, Number of Shares Authorized to be Repurchased | shares |  |  |  |  |  |  | 500,000 |  | 500,000 |
Stock Repurchase Program, Authorized Amount |  |  |  |  | $ 100,000 | $ 50,000 |  |  |  |
Stock Repurchased and Retired During Period, Value | $ 50,000 | $ 61 | $ 463 | $ 118 |  |  |  |  |  |
Stock Repurchased and Retired During Period, Shares | shares |  | 615,000 | 4,628,300 | 1,177,600 |  |  |  |  |  |
Treasury Stock Acquired, Average Cost Per Share | $ / shares |  | $ 23.54 | $ 19.76 | $ 15.68 |  |  |  |  |  |
Common Class B [Member] |  |  |  |  |  |  |  |  |  |
Percentage of Issued and Outstanding Shares |  |  |  |  |  |  |  |  |  | 10.00%

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