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Related Party Transactions (Details) - USD ($) |  |  |  | 3 Months Ended | 9 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | ---
Mar. 31, 2023 | Jan. 26, 2023 | Dec. 02, 2021 | Dec. 29, 2023 | Sep. 29, 2023 | Jun. 30, 2023 | Mar. 31, 2023 | Dec. 23, 2022 | Dec. 23, 2022 | Sep. 22, 2022 | Jun. 24, 2022 | Mar. 25, 2022 | Dec. 24, 2021 | Sep. 24, 2021 | Jun. 25, 2021 | Dec. 29, 2023 | Dec. 23, 2022 | Oct. 02, 2023 | Sep. 11, 2023 | Jul. 01, 2022
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total net sales |  |  |  | $ 254,984,000 | $ 275,509,000 | $ 278,293,000 | $ 269,445,000 | $ 248,789,000 | $ 248,789,000 | $ 237,666,000 | $ 217,753,000 | $ 200,293,000 | $ 186,629,000 | $ 193,610,000 | $ 188,142,000 | $ 808,786,000 | $ 704,208,000 |  |  |
Trade accounts receivable, net | $ 111,290,000 |  |  | 114,324,000 |  |  | 111,290,000 |  |  |  |  |  |  |  |  | 114,324,000 |  |  |  |
Periodic payment |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2,998,000 |  |  |  |
Interest income |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 185,000 |  |  |  |
PSL |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Purchases from related party |  |  |  | 14,982,000 |  |  |  |  | 15,995,000 |  |  |  |  |  |  | 45,714,000 | 45,145,000 |  |  |
Amounts due to related party | 4,682,000 |  |  | 3,128,000 |  |  | 4,682,000 |  |  |  |  |  |  |  |  | 3,128,000 |  |  |  |
PSL | Initial PSL Loan | Loans Payable |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Principal amount |  |  | $ 7,500,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 7,500,000
Interest rate |  |  | 1.26% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Term |  |  | 4 years |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Outstanding balance |  |  |  | 9,375,000 |  |  |  |  |  |  |  |  |  |  |  | 9,375,000 |  |  |  |
PSL | Secondary PSL Loan | Loans Payable |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest rate |  |  | 2.99% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
PSL | Wafer Foundry Agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Purchase commitment period |  | 3 years |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
PSL | Wafer Foundry Agreement, Renewal Term |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related party transaction, term |  | 1 year |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
PSL | Wafer Foundry Agreement, Termination Notice Period |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related party transaction, term |  | 2 years |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
PSL | Wafer Foundry Agreement, Forecast Term |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related party transaction, term |  | 3 years |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
PSL | Wafer Foundry Agreement, Binding Years |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related party transaction, term |  | 2 years |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
PSL | Wafer Foundry Agreement, Mask Pricing Term |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related party transaction, term |  | 2 years |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Crocus Technologies | Initial Crocus Loan | Loans Payable |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Principal amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 3,000,000 | $ 4,000,000 |
Majority Shareholder |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Trade accounts receivable, net | 13,253,000 |  |  |  |  |  | 13,253,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Other accounts receivable from related party | 241,000 |  |  | 102,000 |  |  | 241,000 |  |  |  |  |  |  |  |  | 102,000 |  |  |  |
Amounts due to related party | 0 |  |  | 0 |  |  | 0 |  |  |  |  |  |  |  |  | 0 |  |  |  |
Majority Shareholder | Sanken Distribution Agreement, One-Time Sales Return |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Trade accounts receivable, net | 4,200,000 |  |  | 0 |  |  | $ 4,200,000 |  |  |  |  |  |  |  |  | 0 |  |  |  |
General and administrative expense | 5,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related party transaction amounts | $ 4,200,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Distribution agreement period | 24 months |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Maximum | Crocus Technologies | Initial Crocus Loan | Loans Payable |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Principal amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 7,000,000 |
Related Party Revenue | Majority Shareholder |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total net sales |  |  |  | $ 0 |  |  |  |  | $ 45,117,000 |  |  |  |  |  |  | $ 6,161,000 | $ 131,852,000 |  |  |
Sanken |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ownership percentage by majority shareholder |  |  |  | 51.00% |  |  |  |  |  |  |  |  |  |  |  | 51.00% |  |  |  |
Sanken | Polar Semiconductor, LLC |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ownership percentage by majority shareholder |  |  |  | 70.00% |  |  |  |  |  |  |  |  |  |  |  | 70.00% |  |  |  |
Allegro Microsystems, Inc. | Polar Semiconductor, LLC |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ownership percentage by majority shareholder |  |  |  | 30.00% |  |  |  |  |  |  |  |  |  |  |  | 30.00% |  |  |  |

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