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Summary of Significant Accounting Policies and Other Information - Narrative (Details) customer in Thousands, associate in Thousands, € in Millions | 3 Months Ended | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
Jun. 27, 2020 USD ($) | Jan. 01, 2022 USD ($) country customer associate | Dec. 26, 2020 USD ($) reporting_unit | Dec. 28, 2019 USD ($) | Jan. 01, 2022 EUR (€) country associate | Sep. 25, 2021 | Dec. 26, 2020 EUR (€)
Summary of Significant Accounting Policies and Other Information |  |  |  |  |  |  |
Countries where product is used (country) | country |  | 15 |  |  | 15 |  |
Number of customers (over) | customer |  | 100 |  |  |  |  |
Global associates (associate) | associate |  | 17 |  |  | 17 |  |
Cost of sales |  | $ 1,308,002,000 | $ 944,523,000 | $ 957,578,000 |  |  |
Equity investment |  | 26,070,000 | 19,186,000 |  |  |  |
Gain (loss) from equity method investments |  | 1,300,000 | 0 |  |  |  |
Equity method investments |  | 12,400,000 | 11,400,000 |  |  |  |
Equity method investment, cost |  | 0 | 500,000 |  |  |  |
Impairment of equity method investments |  | 500,000 | 100,000 |  |  |  |
Goodwill impairment |  |  | 33,841,000 |  |  |  |
Goodwill |  | 929,790,000 | $ 816,812,000 | 820,589,000 |  |  |
Number of reporting units | reporting_unit |  |  | 7 |  |  |  |
Trade receivables, allowances |  | 1,900,000 | $ 1,400,000 |  |  |  |
Foreign exchange loss (gain) |  | 17,158,000 | (14,875,000) | 5,224,000 |  |  |
Loss contingency accrual |  | 2,100,000 | 2,900,000 |  | € 1.9 |  | € 2.3
Toll charge, noncurrent |  | 17,800,000 |  |  |  |  |
Toll charge, current |  | (3,000,000) |  |  |  |  |
Transportation Segment |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information |  |  |  |  |  |  |
Goodwill impairment | $ 33,800,000 |  | 33,841,000 |  |  |  |
Goodwill |  | 192,378,000 | 101,931,000 | 131,321,000 |  |  |
90 days past due |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information |  |  |  |  |  |  |
Trade receivables, allowances |  | $ 2,100,000 | 1,000,000 |  |  |  |
Land use rights |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information |  |  |  |  |  |  |
Finite lived intangible asset weighted average useful life (years) |  | 50 years |  |  |  |  |
Electronics – Passive Products and Sensors |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information |  |  |  |  |  |  |
Percentage of fair value in excess of carrying value |  |  |  |  |  | 380.00% |
Electronics – Semiconductor |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information |  |  |  |  |  |  |
Percentage of fair value in excess of carrying value |  |  |  |  |  | 104.00% |
Passenger Car Products |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information |  |  |  |  |  |  |
Percentage of fair value in excess of carrying value |  |  |  |  |  | 255.00% |
Commercial Vehicle Products |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information |  |  |  |  |  |  |
Percentage of fair value in excess of carrying value |  |  |  |  |  | 217.00% |
Automotive Sensors |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information |  |  |  |  |  |  |
Goodwill impairment | $ 33,800,000 |  |  |  |  |  |
Goodwill |  | $ 9,200,000 |  |  |  |  |
Percentage of fair value in excess of carrying value |  |  |  |  |  | 95.00% |
Relay Unit |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information |  |  |  |  |  |  |
Percentage of fair value in excess of carrying value |  |  |  |  |  | 144.00% |
Fuse Unit |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information |  |  |  |  |  |  |
Percentage of fair value in excess of carrying value |  |  |  |  |  | 231.00% |
Minimum | Customer relationships |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information |  |  |  |  |  |  |
Finite lived intangible asset weighted average useful life (years) |  | 5 years |  |  |  |  |
Minimum | Trademarks and tradenames |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information |  |  |  |  |  |  |
Finite lived intangible asset weighted average useful life (years) |  | 5 years |  |  |  |  |
Minimum | Patents, licenses and software |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information |  |  |  |  |  |  |
Finite lived intangible asset weighted average useful life (years) |  | 5 years |  |  |  |  |
Minimum | Distribution network |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information |  |  |  |  |  |  |
Finite lived intangible asset weighted average useful life (years) |  | 4 years |  |  |  |  |
Maximum | Customer relationships |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information |  |  |  |  |  |  |
Finite lived intangible asset weighted average useful life (years) |  | 20 years |  |  |  |  |
Maximum | Trademarks and tradenames |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information |  |  |  |  |  |  |
Finite lived intangible asset weighted average useful life (years) |  | 20 years |  |  |  |  |
Maximum | Patents, licenses and software |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information |  |  |  |  |  |  |
Finite lived intangible asset weighted average useful life (years) |  | 17 years |  |  |  |  |
Maximum | Distribution network |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information |  |  |  |  |  |  |
Finite lived intangible asset weighted average useful life (years) |  | 10 years |  |  |  |  |
Building |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information |  |  |  |  |  |  |
Useful life (in years) |  | 21 years |  |  |  |  |
Equipment | Minimum |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information |  |  |  |  |  |  |
Useful life (in years) |  | 3 years |  |  |  |  |
Equipment | Maximum |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information |  |  |  |  |  |  |
Useful life (in years) |  | 10 years |  |  |  |  |
Furniture and Fixtures |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information |  |  |  |  |  |  |
Useful life (in years) |  | 7 years |  |  |  |  |
Tools, Dies and Molds |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information |  |  |  |  |  |  |
Useful life (in years) |  | 5 years |  |  |  |  |
Computer Equipment |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information |  |  |  |  |  |  |
Useful life (in years) |  | 3 years |  |  |  |  |
Selling, General and Administrative Expenses |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information |  |  |  |  |  |  |
Advertising expense |  | $ 2,100,000 | 2,100,000 | 2,700,000 |  |  |
Selling, General and Administrative Expenses | Shipping and handling cost and expenses |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information |  |  |  |  |  |  |
Cost of sales |  | 15,400,000 | 11,100,000 | $ 11,000,000 |  |  |
Other Assets |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information |  |  |  |  |  |  |
Equity method investment, cost |  |  | 500,000 |  |  |  |
Other Noncurrent Assets |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information |  |  |  |  |  |  |
Marketable securities |  | $ 15,000,000 | $ 13,200,000 |  |  |  |
Polytronics |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information |  |  |  |  |  |  |
Ownership percentage |  | 6.80% | 7.20% |  | 6.80% |  | 7.20%
Equity investment |  | $ 26,100,000 | $ 19,200,000 |  | € 23.0 |  | € 15.7
Powersem | Equity Method |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information |  |  |  |  |  |  |
Ownership percentage |  | 45.00% |  |  | 45.00% |  |
EB Tech | Equity Method |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information |  |  |  |  |  |  |
Ownership percentage |  | 19.00% |  |  | 19.00% |  |
ATEC | Equity Method |  |  |  |  |  |  |
Summary of Significant Accounting Policies and Other Information |  |  |  |  |  |  |
Ownership percentage |  | 24.00% |  |  | 24.00% |  |

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