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Note 1 - Summary of Significant Accounting Policies and Other Information (Details Textual) $ in Thousands, € in Millions | 3 Months Ended | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
Dec. 30, 2017 USD ($) | Dec. 29, 2018 | Dec. 30, 2017 USD ($) | Dec. 31, 2016 USD ($) | Jan. 02, 2016 USD ($) | Dec. 30, 2017 EUR (€) | Oct. 01, 2017 | Dec. 31, 2016 EUR (€)
Number of Reporting Units |  |  | 7 |  |  |  |  |
Finite-Lived Intangible Asset, Useful Life |  |  |  |  |  |  |  |
Foreign Currency Transaction Gain (Loss), before Tax |  |  | $ (2,376) | $ (472) | $ 1,465 |  |  |
Loss Contingency, Accrual, Noncurrent | $ 1,100 |  | $ 1,100 | $ 1,500 |  | € 0.9 |  | € 1.4
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent |  |  | 35.00% | 35.00% | 35.00% |  |  |
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability | 47,000 |  |  |  |  |  |  |
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability, Toll Charge | 49,000 |  | $ 49,000 |  |  |  |  |
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability, Other Than Toll Charge | (2,000) |  | (1,962) |  |  |  |  |
Income Tax Expense (Benefit) |  |  | 84,518 | 18,786 | 26,082 |  |  |
Accounting Standards Update 2016-09 [Member] |  |  |  |  |  |  |  |
Income Tax Expense (Benefit) |  |  | 2,000 |  |  |  |  |
Scenario, Forecast [Member] |  |  |  |  |  |  |  |
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent |  | 21.00% |  |  |  |  |  |
Selling, General and Administrative Expenses [Member] |  |  |  |  |  |  |  |
Advertising Expense |  |  | 2,900 | 2,900 | 2,300 |  |  |
Shipping, Handling and Transportation Costs |  |  | $ 10,900 | $ 9,100 | $ 7,000 |  |  |
Patents, Licenses, and Software [Member] |  |  |  |  |  |  |  |
Finite-Lived Intangible Asset, Useful Life |  |  | 11 years 146 days | 11 years 146 days |  |  |  |
Distribution Rights [Member] |  |  |  |  |  |  |  |
Finite-Lived Intangible Asset, Useful Life |  |  | 12 years 36 days | 12 years 36 days |  |  |  |
Electronics Non Silicon Unit [Member] |  |  |  |  |  |  |  |
Excess Of Fair Value Over Carrying Value Of Invested Capital |  |  |  |  |  |  | 161.00% |
Electronics (Silicon) Unit [Member] |  |  |  |  |  |  |  |
Excess Of Fair Value Over Carrying Value Of Invested Capital |  |  |  |  |  |  | 314.00% |
Passenger Car [Member] |  |  |  |  |  |  |  |
Excess Of Fair Value Over Carrying Value Of Invested Capital |  |  |  |  |  |  | 247.00% |
Commercial Vehicle Products [Member] |  |  |  |  |  |  |  |
Excess Of Fair Value Over Carrying Value Of Invested Capital |  |  |  |  |  |  | 21800.00% |
Sensors [Member] |  |  |  |  |  |  |  |
Excess Of Fair Value Over Carrying Value Of Invested Capital |  |  |  |  |  |  | 10000.00% |
Relay Unit [Member] |  |  |  |  |  |  |  |
Excess Of Fair Value Over Carrying Value Of Invested Capital |  |  |  |  |  |  | 2500.00% |
Fuse Unit [Member] |  |  |  |  |  |  |  |
Excess Of Fair Value Over Carrying Value Of Invested Capital |  |  |  |  |  |  | 24800.00% |
Custom Products Reporting Unit [Member] | Industrial [Member] |  |  |  |  |  |  |  |
Impairment of Intangible Assets (Excluding Goodwill) |  |  |  | $ 6,015 |  |  |  |
Custom Products Reporting Unit [Member] | Customer Relationships [Member] | Industrial [Member] |  |  |  |  |  |  |  |
Impairment of Intangible Assets (Excluding Goodwill) |  |  |  | 2,200 |  |  |  |
Custom Products Reporting Unit [Member] | Trade Names [Member] | Industrial [Member] |  |  |  |  |  |  |  |
Impairment of Intangible Assets (Excluding Goodwill) |  |  |  | $ 3,800 |  |  |  |
Minimum [Member] | Trademarks and Trade Names [Member] |  |  |  |  |  |  |  |
Finite-Lived Intangible Asset, Useful Life |  |  | 5 years |  |  |  |  |
Minimum [Member] | Patents, Licenses, and Software [Member] |  |  |  |  |  |  |  |
Finite-Lived Intangible Asset, Useful Life |  |  | 5 years |  |  |  |  |
Minimum [Member] | Distribution Rights [Member] |  |  |  |  |  |  |  |
Finite-Lived Intangible Asset, Useful Life |  |  | 3 years |  |  |  |  |
Maximum [Member] | Trademarks and Trade Names [Member] |  |  |  |  |  |  |  |
Finite-Lived Intangible Asset, Useful Life |  |  | 20 years |  |  |  |  |
Maximum [Member] | Patents, Licenses, and Software [Member] |  |  |  |  |  |  |  |
Finite-Lived Intangible Asset, Useful Life |  |  | 17 years |  |  |  |  |
Maximum [Member] | Distribution Rights [Member] |  |  |  |  |  |  |  |
Finite-Lived Intangible Asset, Useful Life |  |  | 20 years |  |  |  |  |
Building [Member] |  |  |  |  |  |  |  |
Property, Plant and Equipment, Useful Life |  |  | 21 years |  |  |  |  |
Equipment [Member] | Minimum [Member] |  |  |  |  |  |  |  |
Property, Plant and Equipment, Useful Life |  |  | 7 years |  |  |  |  |
Equipment [Member] | Maximum [Member] |  |  |  |  |  |  |  |
Property, Plant and Equipment, Useful Life |  |  | 9 years |  |  |  |  |
Furniture and Fixtures [Member] |  |  |  |  |  |  |  |
Property, Plant and Equipment, Useful Life |  |  | 7 years |  |  |  |  |
Tools, Dies and Molds [Member] |  |  |  |  |  |  |  |
Property, Plant and Equipment, Useful Life |  |  | 5 years |  |  |  |  |
Computer Equipment [Member] |  |  |  |  |  |  |  |
Property, Plant and Equipment, Useful Life |  |  | 3 years |  |  |  |  |
Other Noncurrent Assets [Member] |  |  |  |  |  |  |  |
Marketable Securities | $ 8,000 |  | $ 8,000 |  |  |  |  |
Polytronics [Member] |  |  |  |  |  |  |  |
Long-term Investment, Ownership Percentage | 7.20% |  | 7.20% | 7.20% |  | 7.20% |  | 7.20%
Marketable Securities, Equity Securities | $ 11,000 |  | $ 11,000 | $ 10,400 |  | € 9.2 |  | € 10.0
Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, before Tax |  |  | $ (1,000) | $ (800) |  |  |  |

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