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Related Party Transactions (Details) - USD ($) |  |  |  |  | 12 Months Ended |
--- | --- | --- | --- | --- | --- | ---
Apr. 25, 2024 | Mar. 31, 2023 | Jan. 26, 2023 | Dec. 02, 2021 | Mar. 29, 2024 | Mar. 31, 2023 | Mar. 25, 2022 | Jul. 02, 2022
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |
Net sales |  |  |  |  | $ 1,049,367,000 | $ 973,653,000 | $ 768,674,000 |
Trade accounts receivable, net |  | $ 111,290,000 |  |  | 118,508,000 | 111,290,000 |  |
Outstanding balance |  | 25,000,000 |  |  | 245,102,000 | 25,000,000 |  |
Interest income |  |  |  |  | 237,000 |  |  |
Periodic payment |  |  |  |  | 3,987,000 |  |  |
Sanken Distribution Agreement, One-Time Sales Return |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |
Trade accounts receivable, net |  | 13,253,000 |  |  |  | 13,253,000 |  |
Sanken |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |
Other accounts receivable from related party |  | 241,000 |  |  | 160,000 | 241,000 |  |
Sanken | Sanken Distribution Agreement, One-Time Sales Return |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |
Trade accounts receivable, net |  | 4,200,000 |  |  |  | 4,200,000 |  |
General and administrative expense |  | 5,000,000 |  |  |  |  |  |
Related party transaction amounts |  | $ 4,200,000 |  |  |  |  |  |
Distribution agreement period |  | 24 months |  |  |  |  |  |
PSL |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |
Amounts due to related party |  | $ 4,682,000 |  |  | 1,621,000 | 4,682,000 |  |
Purchases from related party |  |  |  |  | 60,426,000 | 58,056,000 |  |
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 |  |  |  |  | 8,438,000 |  |  |
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 |  |  |  |  |
Related Party Revenue | Sanken |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |
Net sales |  |  |  |  | $ 6,161,000 | $ 160,763,000 |  |
Sanken |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |
Ownership percentage by majority shareholder |  |  |  |  | 51.00% |  |  |
Polar Semiconductor, LLC | Sanken |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |
Ownership percentage by majority shareholder |  |  |  |  | 70.00% |  |  |
Polar Semiconductor, LLC | Allegro Microsystems, Inc. |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |
Ownership percentage by majority shareholder |  |  |  |  | 30.00% |  |  |
Polar Semiconductor, LLC | Subsequent Event |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |
Exchange for equity interests amounts of transaction | $ 175,000 |  |  |  |  |  |  |
Additional direct funding and tax credits amount | $ 310,700 |  |  |  |  |  |  |
Polar Semiconductor, LLC | Subsequent Event | Allegro Microsystems, Inc. |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |
Ownership percentage by majority shareholder | 10.20% |  |  |  |  |  |  |

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