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v3.19.3.a.u2

Segment Information - Narrative (Details) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 28, 2019 USD ($) | Sep. 28, 2019 USD ($) | Jun. 29, 2019 USD ($) | Mar. 30, 2019 USD ($) | Dec. 29, 2018 USD ($) | Sep. 29, 2018 USD ($) | Jun. 30, 2018 USD ($) | Mar. 31, 2018 USD ($) | Dec. 28, 2019 USD ($) segment | Dec. 29, 2018 USD ($) | Dec. 30, 2017 USD ($)
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Number of operating segments | segment |  |  |  |  |  |  |  |  | 3 |  |
Acquisition related costs | $ 1,900 | $ 3,200 | $ 1,500 | $ 2,400 | $ 3,200 | $ 2,900 | $ 2,400 | $ 11,700 |  |  |
Restructuring charges primarily related to employee termination costs | 2,100 | $ 2,500 | 5,700 |  |  |  |  |  | $ 13,033 | $ 12,583 |
Backlog amortization costs |  |  |  |  |  |  |  | 2,500 |  |  |
Total restructuring charges |  |  |  |  |  |  |  |  | 12,711 | 10,365 | $ 2,227
Stock compensation expense |  |  |  |  |  |  |  |  | 19,046 | 27,431 | 16,315
Allocated share based compensation |  |  |  |  |  |  |  |  | 19,900 | 28,200 | 17,300
Impairment charges | $ 4,200 |  | $ 200 | $ 2,800 |  |  |  |  | $ 322 | $ 2,218 | $ 0
Net sales | Geographic Concentration Risk | Outside the United States |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Concentration risk (less than) |  |  |  |  |  |  |  |  | 71.00% | 70.00% | 69.00%
Net sales | Geographic Concentration Risk | China |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Concentration risk (less than) |  |  |  |  |  |  |  |  | 28.00% | 27.00% | 26.00%
Net sales | Customer Concentration Risk | Arrow Electronics Inc. |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Concentration risk (less than) |  |  |  |  |  |  |  |  | 10.70% | 10.70% | 10.60%
Selling, General and Administrative Expenses |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Acquisition related costs |  |  |  |  |  |  |  |  | $ 2,700 |  |
Other | Operating Income (Loss) |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Acquisition related costs |  |  |  |  |  |  |  |  | 8,900 | $ 88,700 |
Inventory adjustment |  |  |  |  |  |  |  |  |  | 36,900 |
Legal, accounting and other expenses |  |  |  |  |  |  |  |  |  | 18,700 |
Backlog amortization costs |  |  |  |  |  |  |  |  |  | 12,400 |
Total restructuring charges |  |  |  |  |  |  |  |  |  | 8,300 |
Change in control expense |  |  |  |  |  |  |  |  |  | 2,100 |
Impairment charges |  |  |  |  |  |  |  |  |  | 5,800 |
Other | Selling, General and Administrative Expenses |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Acquisition related costs |  |  |  |  |  |  |  |  |  |  | $ 8,000
Total restructuring charges |  |  |  |  |  |  |  |  |  |  | $ 2,200
IXYS Corporation |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Acquisition related costs |  |  |  |  |  |  |  |  | $ 2,200 | $ 11,000 |
Backlog amortization costs |  |  |  |  | $ 3,700 | $ 3,100 | $ 3,100 |  |  |  |
IXYS Corporation | Selling, General and Administrative Expenses |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Stock compensation expense |  |  |  |  |  |  |  | $ 4,500 |  |  |

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