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Segment Information - Narrative (Details) $ in Thousands | 1 Months Ended | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Apr. 30, 2019 USD ($) | Dec. 26, 2020 USD ($) | Sep. 26, 2020 USD ($) | Jun. 27, 2020 USD ($) | Mar. 28, 2020 USD ($) | Dec. 28, 2019 USD ($) | Sep. 28, 2019 USD ($) | Jun. 29, 2019 USD ($) | Mar. 30, 2019 USD ($) | Jun. 30, 2018 USD ($) | Dec. 26, 2020 USD ($) segment | Dec. 28, 2019 USD ($) | Dec. 29, 2018 USD ($)
Segment Reporting Information |  |  |  |  |  |  |  |  |  |  |  |  |
Number of operating segments | segment |  |  |  |  |  |  |  |  |  |  | 3 |  |
Acquisition related costs |  | $ 700 | $ 300 | $ 100 | $ 1,200 | $ 1,900 | $ 3,200 | $ 1,500 | $ 2,400 |  |  |  |
Restructuring, impairment and other costs |  | $ 800 | 1,300 | 1,800 |  | 2,100 | $ 2,500 | 5,700 |  |  | $ 41,716 | $ 13,033 | $ 12,583
Other asset impairment charges |  |  |  | $ 33,800 | 1,900 |  |  |  |  |  |  |  |
Restructuring charges |  |  |  |  |  |  |  |  |  |  | 5,638 | 12,711 | 10,365
Stock compensation expense |  |  |  |  |  |  |  |  |  |  | 18,129 | 19,046 | 27,431
Impairment charges |  |  | $ 100 |  |  | $ 4,200 |  | $ 200 | $ 2,800 |  | 36,078 | 322 | 2,218
Automotive |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information |  |  |  |  |  |  |  |  |  |  |  |  |
Restructuring, impairment and other costs |  |  |  |  |  |  |  |  |  |  | 34,698 | 6,287 | 914
Other asset impairment charges |  |  |  |  | $ 2,200 |  |  |  |  |  |  |  |
Restructuring charges |  |  |  |  |  |  |  |  |  |  | 857 | 5,965 | 826
Impairment charges |  |  |  |  |  |  |  |  |  |  | 33,841 | 322 | 88
Other restructuring charges |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information |  |  |  |  |  |  |  |  |  |  |  |  |
Restructuring charges | $ 1,400 |  |  |  |  |  |  |  |  |  | 185 | 2,352 | 862
Other restructuring charges | Automotive |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information |  |  |  |  |  |  |  |  |  |  |  |  |
Restructuring charges |  |  |  |  |  |  |  |  |  |  | 175 | 1,714 | 192
Employee terminations |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information |  |  |  |  |  |  |  |  |  |  |  |  |
Restructuring charges | $ 1,700 |  |  |  |  |  |  |  |  |  | 5,453 | 10,359 | 9,503
Employee terminations | Automotive |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information |  |  |  |  |  |  |  |  |  |  |  |  |
Restructuring charges |  |  |  |  |  |  |  |  |  |  | $ 682 | $ 4,251 | $ 634
Net sales | Geographic Concentration Risk | Outside the United States |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information |  |  |  |  |  |  |  |  |  |  |  |  |
Concentration risk (less than) |  |  |  |  |  |  |  |  |  |  | 73.00% | 71.00% | 70.00%
Net sales | Geographic Concentration Risk | China |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information |  |  |  |  |  |  |  |  |  |  |  |  |
Concentration risk (less than) |  |  |  |  |  |  |  |  |  |  | 30.00% | 28.00% | 27.00%
Net sales | Customer Concentration Risk | Arrow Electronics Inc. |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information |  |  |  |  |  |  |  |  |  |  |  |  |
Concentration risk (less than) |  |  |  |  |  |  |  |  |  |  | 10.40% | 10.70% | 10.70%
Operating Income (Loss) |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisition related costs |  |  |  |  |  |  |  |  |  |  |  | $ 8,900 |
Restructuring charges |  |  |  |  |  |  |  |  |  |  | $ 5,500 |  |
Other | Operating Income (Loss) |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisition related costs |  |  |  |  |  |  |  |  |  |  | $ 2,300 |  | $ 88,700
Restructuring, impairment and other costs |  |  |  |  |  |  |  |  |  |  |  |  | 5,800
Restructuring charges |  |  |  |  |  |  |  |  |  |  |  |  | 8,300
Inventory adjustment |  |  |  |  |  |  |  |  |  |  |  |  | 36,900
Legal, accounting and other expenses |  |  |  |  |  |  |  |  |  |  |  |  | 18,700
Backlog amortization costs |  |  |  |  |  |  |  |  |  |  |  |  | 12,400
Change in control expense |  |  |  |  |  |  |  |  |  |  |  |  | 2,100
Other | Operating Income (Loss) | Other restructuring charges |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information |  |  |  |  |  |  |  |  |  |  |  |  |
Impairment charges |  |  |  |  |  |  |  |  |  |  |  |  | 2,200
IXYS Corporation |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisition related costs |  |  |  |  |  |  |  |  |  |  |  |  | 11,000
Inventory adjustment |  |  |  |  |  |  |  |  |  | $ 36,900 |  |  |
Stock compensation expense |  |  |  |  |  |  |  |  |  |  |  |  | $ 4,500
IXYS Corporation | Employee terminations |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information |  |  |  |  |  |  |  |  |  |  |  |  |
Restructuring charges |  |  |  |  |  |  |  |  |  |  |  | $ 13,000 |

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