Percentage of vesting of award under share-based payment arrangement based on market conditions.

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The yearly percentage of grants tested for award vesting rights under share based payment arrangement.

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The percentage of market condition achieved for awards to vest under share based payment arrangement.

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The maximum annual contribution percentage per employee that can be used under the plan.

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The number of shares transferred out under the share-based compensation arrangement.

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Represents share ratio of share-based compensation arrangement by share-based payment award.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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Amount of cost to be recognized for option under share-based payment arrangement.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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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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Number of shares authorized for issuance under share-based payment arrangement.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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Gross number of share options (or share units) granted during the period.

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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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Percentage of vesting of award under share-based payment arrangement.

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Purchase price of common stock expressed as a percentage of its fair value.

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No definition available.

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Note 10 - Stock-Based Compensation Plans (Details Textual) $ / shares in Units, $ in Thousands		1 Months Ended	3 Months Ended						12 Months Ended
	May 31, 2012 shares	May 31, 2012 shares	Jan. 02, 2021 USD ($) shares	Sep. 26, 2020	Sep. 26, 2020	Jun. 27, 2020	Mar. 28, 2020 USD ($)	Mar. 30, 2019 USD ($)	Jan. 02, 2021 USD ($) $ / shares shares	Dec. 28, 2019 USD ($) $ / shares shares	Dec. 31, 2018 USD ($)	Dec. 29, 2018 USD ($) $ / shares
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)									4 years
Share-based Payment Arrangement, Expense									$ 40,372	$ 18,899	$ 13,646
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in shares) \| shares									0	0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value									$ 21,500	$ 17,800		$ 6,500
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share) \| $ / shares									$ 2.73
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share) \| $ / shares									$ 6.62	$ 1.69		$ 1.50
Employee and Director Stock Options [Member]
Share-based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount			$ 1,000						$ 1,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)									8 months 12 days
Share-based Payment Arrangement, Option [Member]
Share-based Payment Arrangement, Expense									$ 2,000	$ 2,400		$ 4,100
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share) \| $ / shares									$ 26.48
Chief Executive Officer [Member]
Share-based Payment Arrangement, Expense								$ 1,400
Chief Executive Officer [Member] \| Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)							3 years
Share-based Payment Arrangement, Expense									$ 16,600	10,300		8,000
Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount			$ 44,300						$ 44,300
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage Of Grants Tested Each Year							50.00%
Executive Officer [Member] \| Restricted Stock Units (RSUs) [Member]
Share-based Payment Arrangement, Expense							$ 1,800
Executive Officer [Member] \| Restricted Stock Units (RSUs) [Member] \| Share-based Payment Arrangement, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage Of Market Condition Achieved							75.00%
Executive Officer [Member] \| Restricted Stock Units (RSUs) [Member] \| Share-based Payment Arrangement, Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage, Based on Market Conditions							100.00%
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage Of Market Condition Achieved							55.00%
Executive Officer [Member] \| Restricted Stock Units (RSUs) [Member] \| Share-based Payment Arrangement, Tranche Three [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage Of Market Condition Achieved							25.00%
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage							0.00%
Executive Officer [Member] \| Restricted Stock Units (RSUs) [Member] \| Minimum [Member] \| TSR Relative To PHLX Semiconductor Sector Index, 75th Percentile [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage, Based on Market Conditions							250.00%
Executive Officer [Member] \| Restricted Stock Units (RSUs) [Member] \| Minimum [Member] \| Share-based Payment Arrangement, Tranche Three [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage Of Market Condition Achieved							25.00%
Executive Officer [Member] \| Restricted Stock Units (RSUs) [Member] \| Maximum [Member] \| TSR Relative To PHLX Semiconductor Sector Index, 75th Percentile [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage, Based on Market Conditions							200.00%
Executive Officer [Member] \| Restricted Stock Units (RSUs) [Member] \| Maximum [Member] \| Share-based Payment Arrangement, Tranche Three [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage Of Market Condition Achieved							75.00%
Executive Officer [Member] \| Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)									3 years
Share-based Payment Arrangement, Expense									$ 20,800	$ 5,700		$ 900
Executive Officer [Member] \| Performance Shares [Member] \| TSR Relative To PHLX Semiconductor Sector Index, 75th Percentile [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage, Based on Market Conditions									100.00%
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage Of Market Condition Achieved									50.00%
Executive Officer [Member] \| Performance Shares [Member] \| TSR Relative To PHLX Semiconductor Sector Index, 25th Percentile [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage, Based on Market Conditions									0.00%
Executive Officer [Member] \| Performance Shares [Member] \| Minimum [Member] \| TSR Relative To PHLX Semiconductor Sector Index, 75th Percentile [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage, Based on Market Conditions									200.00%
Executive Officer [Member] \| Performance Shares [Member] \| Minimum [Member] \| TSR Relative To PHLX Semiconductor Sector Index, 25th Percentile [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage, Based on Market Conditions									0.00%
Executive Officer [Member] \| Performance Shares [Member] \| Maximum [Member] \| TSR Relative To PHLX Semiconductor Sector Index, 75th Percentile [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage, Based on Market Conditions									250.00%
Executive Officer [Member] \| Performance Shares Granted in 2018 [Member] \| Share-based Payment Arrangement, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage, Based on Market Conditions						33.30%	200.00%
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage Of Market Condition Achieved			75.00%	75.00%			75.00%
Executive Officer [Member] \| Performance Shares Granted in 2018 [Member] \| Minimum [Member] \| Share-based Payment Arrangement, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage, Based on Market Conditions					250.00%
Executive Officer [Member] \| Performance Shares Granted in 2018 [Member] \| Maximum [Member] \| Share-based Payment Arrangement, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage, Based on Market Conditions					200.00%
The2012 ESPP [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares) \| shares	3.0	3.0
Share-based Compensation Arrangement By Share-based Payment Award, Maximum, Annual Contribution Per Employee, Percent	10.00%
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent		85.00%
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in shares) \| shares			1,200,000						1,200,000
Share-based Compensation Arrangement by Share-based Payment Award, Number Of Shares, Transferred Out (in shares) \| shares									2,000,000.0
The 2013 Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in shares) \| shares			11,600,000						11,600,000
Share-based Compensation Arrangement by Share-based Payment Award, Share Ratio			2.2						2.2