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Note 10 - Shareholders' Equity (Details Textual) - USD ($) $ / shares in Units, $ in Thousands | 3 Months Ended | 12 Months Ended |  |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | ---
Apr. 02, 2017 | Dec. 31, 2017 | Jan. 01, 2017 | Jan. 03, 2016 | Jul. 02, 2017 | Jul. 03, 2016 | Nov. 19, 2015 | May 31, 2015 | Oct. 07, 2014 | Mar. 05, 2012
Common Stock, Shares Authorized |  |  |  |  |  |  |  |  |  | 120,000,000
Common Stock, Par or Stated Value Per Share |  |  |  |  |  |  |  |  |  | $ 0.10
Common Stock, Dividends, Per Share, Cash Paid |  | $ 0.25 | $ 0.22 | $ 0.18 |  |  |  |  |  |
Stock Repurchase Program, Remaining Authorized Repurchase Amount |  | $ 39,500 |  |  |  |  |  |  |  |
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 |  |  |  |  |  |  |  | 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 |  | 2 years |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term |  | 2 years |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value |  | $ 1,400 |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value |  | $ 1,400 |  |  |  |  |  |  |  |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Lower Range Limit |  | $ 4.31 |  |  |  |  |  |  |  |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Upper Range Limit |  | $ 13.04 |  |  |  |  |  |  |  |
Employee Stock Option [Member] |  |  |  |  |  |  |  |  |  |
Allocated Share-based Compensation Expense |  | $ 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 |  | $ 2,800 | $ 4,700 | $ 13,900 |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period |  | 253,000 | 277,000 | 597,000 |  |  |  |  |  |
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options |  | $ 4,100 |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number |  | 468,000 | 505,000 |  |  |  |  |  |  |
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 |  | $ 4,500 | $ 1,200 |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period |  | 354,000 |  | 0 |  |  |  |  |  |
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 |  | $ 6,100 |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number |  | 669,500 | 368,500 | 0 |  |  |  |  |  |
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 |  | $ 2,600 | $ 2,000 |  |  |  |  |  |  |
Common Stock [Member] |  |  |  |  |  |  |  |  |  |
Stock Repurchase Program, Number of Shares Authorized to be Repurchased |  |  |  |  |  |  | 500,000 |  | 500,000 |
Stock Repurchase Program, Authorized Amount |  |  |  |  | $ 100,000 | $ 50,000 |  |  |  |
Stock Repurchased and Retired During Period, Value | $ 50,000 | $ 463 | $ 118 | $ 65 |  |  |  |  |  |
Stock Repurchased and Retired During Period, Shares |  | 4,628,300 | 1,177,600 | 650,000 |  |  |  |  |  |
Treasury Stock Acquired, Average Cost Per Share |  | $ 19.76 | $ 15.68 | $ 20.47 |  |  |  |  |  |
Common Class B [Member] |  |  |  |  |  |  |  |  |  |
Percentage of Issued and Outstanding Shares |  |  |  |  |  |  |  |  |  | 10.00%

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- Definition The number of grants made 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). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (e)(1) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition Number of shares that have been repurchased and retired during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(28)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21463-112644 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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