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Summary of Significant Accounting Policies and Other Information - Narrative (Details) $ in Thousands, € in Millions |  | 3 Months Ended | 12 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | ---
Jan. 17, 2018 USD ($) | Dec. 28, 2019 USD ($) | Jun. 29, 2019 USD ($) | Mar. 30, 2019 USD ($) | Dec. 29, 2018 USD ($) | Sep. 29, 2018 USD ($) | Dec. 30, 2017 USD ($) | Dec. 28, 2019 USD ($) unit | Dec. 29, 2018 USD ($) | Jan. 17, 2018 USD ($) | Dec. 30, 2017 USD ($) | Dec. 28, 2019 EUR (€) | Dec. 28, 2019 USD ($) | Sep. 30, 2019 | Dec. 30, 2018 USD ($) | Dec. 29, 2018 EUR (€) | Dec. 29, 2018 USD ($)
Summary of Significant Accounting Policies and Other Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Investments in equity securities |  |  |  |  |  |  |  |  |  |  |  |  | $ 12,969 |  |  |  | $ 10,312
Gain from equity method investments |  |  |  |  |  |  |  | $ (600) | $ 700 |  |  |  |  |  |  |  |
Equity method investments |  |  |  |  |  |  |  |  |  |  |  |  | 11,100 |  |  |  | 11,600
Cost method investments |  |  |  |  |  |  |  |  |  |  |  |  | 400 |  |  |  | 7,900
Impairment charges |  | $ 4,200 | $ 200 | $ 2,800 |  |  |  | $ 322 | 2,218 |  | $ 0 |  |  |  |  |  |
Number of reporting units | unit |  |  |  |  |  |  |  | 7 |  |  |  |  |  |  |  |  |
Foreign exchange loss (gain) |  |  |  |  |  |  |  | $ 5,224 | (863) |  | 2,376 |  |  |  |  |  |
Loss contingency accrual |  |  |  |  |  |  |  |  |  |  |  | € 0.6 | 700 |  |  | € 1.1 | 1,300
Provisional estimate of Tax Act |  |  |  |  |  |  | $ 47,000 |  |  |  |  |  |  |  |  |  |
Preliminary estimate of toll charge |  |  |  |  |  |  | 49,000 |  |  |  | 49,000 |  |  |  |  |  |
Other net tax benefits |  |  |  |  |  |  | $ (2,000) |  |  |  |  |  |  |  |  |  |
TCJA one-time charge |  |  |  |  | $ 3,200 |  |  |  |  |  |  |  |  |  |  |  |
Toll charge, noncurrent |  |  |  |  |  |  |  | (23,800) |  |  |  |  |  |  |  |  |
Toll charge, current |  |  |  |  |  |  |  | 3,000 |  |  |  |  |  |  |  |  |
Operating ROU assets |  |  |  |  |  |  |  |  |  |  |  |  | 21,918 |  |  |  | 0
Operating lease liability |  |  |  |  |  |  |  |  |  |  |  |  | 24,425 |  |  |  |
ASU 2016-02 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Operating ROU assets |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 26,100 |  |
Operating lease liability |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 29,400 |  |
ASU 2016-01 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cumulative effect adjustment |  |  |  |  |  |  |  | (9,800) |  |  |  |  |  |  |  |  |
Loss recognized on statement of income |  |  |  |  |  |  |  |  | (700) |  |  |  |  |  |  |  |
Other Expense |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Investments in equity securities |  |  |  |  |  |  |  |  |  |  |  |  | 400 |  |  |  |
Impairment charges |  |  |  |  |  |  |  | 7,300 |  |  |  |  |  |  |  |  |
Selling, General and Administrative Expenses |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Advertising expense |  |  |  |  |  |  |  | 2,700 | 2,800 |  | 2,900 |  |  |  |  |  |
Shipping and handling fees and costs |  |  |  |  |  |  |  | 11,000 | 12,300 |  | $ 10,900 |  |  |  |  |  |
Industrial |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Impairment charges |  |  |  |  |  |  |  | $ 0 | $ 2,130 |  |  |  |  |  |  |  |
Electronics Non Silicon Unit |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Excess fair value over carrying value |  |  |  |  |  |  |  |  |  |  |  |  |  | 217.00% |  |  |
Electronics (Silicon) Unit |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Excess fair value over carrying value |  |  |  |  |  |  |  |  |  |  |  |  |  | 42.00% |  |  |
Passenger Car |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Excess fair value over carrying value |  |  |  |  |  |  |  |  |  |  |  |  |  | 137.00% |  |  |
Commercial Vehicle Products |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Excess fair value over carrying value |  |  |  |  |  |  |  |  |  |  |  |  |  | 213.00% |  |  |
Sensors |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Excess fair value over carrying value |  |  |  |  |  |  |  |  |  |  |  |  |  | 40.00% |  |  |
Relay Unit |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Excess fair value over carrying value |  |  |  |  |  |  |  |  |  |  |  |  |  | 89.00% |  |  |
Fuse Unit |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Excess fair value over carrying value |  |  |  |  |  |  |  |  |  |  |  |  |  | 268.00% |  |  |
Minimum | Trademarks and tradenames |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Weighted average useful life (years) |  |  |  |  |  |  |  | 5 years |  |  |  |  |  |  |  |  |
Minimum | Patents, licenses and software |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Weighted average useful life (years) |  |  |  |  |  |  |  | 5 years |  |  |  |  |  |  |  |  |
Minimum | Distribution network |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Weighted average useful life (years) |  |  |  |  |  |  |  | 4 years |  |  |  |  |  |  |  |  |
Maximum | Trademarks and tradenames |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Weighted average useful life (years) |  |  |  |  |  |  |  | 20 years |  |  |  |  |  |  |  |  |
Maximum | Patents, licenses and software |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Weighted average useful life (years) |  |  |  |  |  |  |  | 17 years |  |  |  |  |  |  |  |  |
Maximum | Distribution network |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Weighted average useful life (years) |  |  |  |  |  |  |  | 10 years |  |  |  |  |  |  |  |  |
Building |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Useful life |  |  |  |  |  |  |  | 21 years |  |  |  |  |  |  |  |  |
Equipment | Minimum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Useful life |  |  |  |  |  |  |  | 3 years |  |  |  |  |  |  |  |  |
Equipment | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Useful life |  |  |  |  |  |  |  | 10 years |  |  |  |  |  |  |  |  |
Furniture and Fixtures |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Useful life |  |  |  |  |  |  |  | 7 years |  |  |  |  |  |  |  |  |
Tools, Dies and Molds |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Useful life |  |  |  |  |  |  |  | 5 years |  |  |  |  |  |  |  |  |
Computer Equipment |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Useful life |  |  |  |  |  |  |  | 3 years |  |  |  |  |  |  |  |  |
Other Noncurrent Assets |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Marketable securities |  |  |  |  |  |  |  |  |  |  |  |  | $ 10,500 |  |  |  | 9,100
ATEC |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ownership percentage |  |  |  |  |  |  |  |  |  |  |  | 24.00% | 24.00% |  |  |  |
EB Tech |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ownership percentage |  |  |  |  |  |  |  |  |  |  |  | 19.00% | 19.00% |  |  |  |
Powersem |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ownership percentage |  |  |  |  |  |  |  |  |  |  |  | 45.00% | 45.00% |  |  |  |
Polytronics |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Investments in equity securities |  |  |  |  |  |  |  |  |  |  |  | € 11.6 | $ 12,800 |  |  | € 8.9 | $ 10,200
Ownership percentage |  |  |  |  |  |  |  |  |  |  |  | 7.20% | 7.20% |  |  |  |
Toll Charge |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
TCJA one-time charge |  |  |  |  | 2,300 |  |  |  |  |  |  |  |  |  |  |  |
Other Items |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
TCJA one-time charge |  |  |  |  | 900 |  |  |  |  |  |  |  |  |  |  |  |
IXYS Corporation | Toll Charge |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
TCJA one-time charge | $ 7,000 |  |  |  | $ (1,000) | $ (2,000) |  |  |  | $ 7,000 |  |  |  |  |  |  |

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