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Summary of Significant Accounting Policies - Concentrations of Credit Risk and Significant Customers (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Sep. 24, 2021 | Sep. 25, 2020 | Sep. 24, 2021 | Sep. 25, 2020 | Mar. 26, 2021 | Mar. 27, 2021
Concentration Risk [Line Items] |  |  |  |  |  |
Operating lease right-of-use assets | $ 17,054 |  | $ 17,054 |  | $ 0 |
Total operating lease liabilities | $ 17,316 |  | $ 17,316 |  |  |
Accounting Standards Update 2016-02 |  |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |  |
Operating lease right-of-use assets |  |  |  |  |  | $ 18,403
Total operating lease liabilities |  |  |  |  |  | $ 18,759
Revenue Benchmark | Geographic Concentration Risk | Non-US |  |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |  |
Concentration risk, percentage | 85.60% | 84.70% | 85.70% | 86.50% |  |
Revenue Benchmark | Geographic Concentration Risk | Greater China |  |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |  |
Concentration risk, percentage | 26.20% | 27.80% | 24.50% | 27.80% |  |
Revenue Benchmark | Geographic Concentration Risk | Japan |  |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |  |
Concentration risk, percentage | 19.20% | 16.40% | 19.00% | 18.30% |  |
Revenue Benchmark | Geographic Concentration Risk | South Korea |  |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |  |
Concentration risk, percentage | 10.20% |  | 10.90% | 10.40% |  |
Sanken | Trade Accounts Receivable | Customer Concentration Risk |  |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |  |
Concentration risk, percentage |  |  | 24.30% |  | 22.70% |
Sanken | Revenue Benchmark | Customer Concentration Risk |  |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |  |
Concentration risk, percentage | 19.20% | 16.50% | 19.00% | 18.30% |  |

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