The number of authorized stock that is reduced by the issuance of other than stock option awards.

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The percentage of total issued and outstanding shares represented by a class of stock.

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The maximum percentage of the shares issued compared to the unit amount of the equity instruments, other than options, that are exercised to acquire the shares issued.

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The rate at which an employee stock option is exercisable.

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Aggregate dividends paid during the period for each share of common stock outstanding.

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Face amount or stated value per share of common stock.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Unrecognized cost of unvested share-based compensation awards.

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

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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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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 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).

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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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.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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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.

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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.

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Amount of stock repurchase plan authorized.

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The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

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Amount remaining of a stock repurchase plan authorized.

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Number of shares that have been repurchased and retired during the period.

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Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

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Total cost of shares repurchased divided by the total number of shares repurchased.

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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%