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Related Party Transactions (Details) - USD ($) |  |  |  |  |  |  |  |  |  | 3 Months Ended | 9 Months Ended |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Sep. 20, 2024 | Aug. 07, 2024 | Jul. 29, 2024 | Jul. 26, 2024 | Jul. 24, 2024 | Jul. 23, 2024 | Apr. 25, 2024 | Jul. 01, 2022 | Dec. 02, 2021 | Dec. 27, 2024 | Dec. 29, 2023 | Dec. 27, 2024 | Dec. 29, 2023 | Mar. 29, 2024
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net proceeds from issuance of common stock |  |  |  |  |  |  |  |  |  |  |  | $ 665,850,000 | $ 0 |
Repurchase of common stock aggregate consideration , value |  |  |  |  |  |  |  |  |  |  |  | 821,199,000 |  |
Recognized loss of fair value forward repurchase contract |  |  |  |  |  |  |  |  |  | $ 0 | $ 0 | 34,752,000 | 0 |
Trade accounts receivable, net |  |  |  |  |  |  |  |  |  | 83,805,000 |  | 83,805,000 |  | $ 118,508,000
Outstanding balance |  |  |  |  |  |  |  |  |  | 368,671,000 |  | 368,671,000 |  | 245,102,000
Periodic payment |  |  |  |  |  |  |  |  |  |  |  | 1,964,000 |  |
Interest income |  |  |  |  |  |  |  |  |  |  |  | $ 89,000 |  |
Share Repurchase Agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Facilitation fee included in transaction expenses |  |  |  |  |  | $ 35,000,000 |  |  |  |  |  |  |  |
Facilitation fee |  |  | $ 35,000,000 |  |  |  |  |  |  |  |  |  |  |
Common Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Repurchase of common stock |  |  |  |  |  |  |  |  |  |  |  | 38,767,315 |  |
Issuance of common stock |  |  |  |  |  |  |  |  |  |  |  | 28,750,000 |  |
Repurchase of common stock aggregate consideration , value |  |  |  |  |  |  |  |  |  |  |  | $ 388,000 |  |
Common Stock | Share Repurchase Agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Repurchase of common stock |  | 10,017,315 | 28,750,000 |  |  | 38,767,315 |  |  |  |  |  |  |  |
Repurchase of common stock aggregate consideration , value |  | $ 225,549,000 | $ 628,256,000 |  |  |  |  |  |  |  |  |  |  |
Common Stock | Equity Offering |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Issuance of common stock |  |  |  | 28,750,000 | 25,000,000 |  |  |  |  |  |  |  |  |
Share price |  |  |  | $ 24 | $ 23.16 |  |  |  |  |  |  |  |  |
Net proceeds from issuance of common stock |  |  |  | $ 665,850,000 |  |  |  |  |  |  |  |  |  |
Underwriting discount |  |  |  | $ 24,150,000 |  |  |  |  |  |  |  |  |  |
Common Stock | Equity Offering | Minimum |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net proceeds from issuance of common stock |  |  |  |  |  | $ 300,000,000 |  |  |  |  |  |  |  |
Common Stock | Underwriters Option |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Issuance of common stock |  |  |  |  | 3,750,000 |  |  |  |  |  |  |  |  |
Polar Semiconductor, LLC |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss on extinguishment of debt | $ 2,804,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Extinguishment of Debt, Amount | 10,350,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Exchange for equity interests amounts of transaction |  |  |  |  |  |  | $ 175,000,000 |  |  |  |  |  |  |
PSL |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Purchases from related party |  |  |  |  |  |  |  |  |  | 11,533,000 | $ 14,982,000 | 40,867,000 | $ 45,714,000 |
Amounts due to related party |  |  |  |  |  |  |  |  |  | 2,102,000 |  | 2,102,000 |  | 1,621,000
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 |  |  |  |  |
PSL | Secondary PSL Loan | Loans Payable |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest rate |  |  |  |  |  |  |  | 2.99% |  |  |  |  |  |
Term |  |  |  |  |  |  |  | 4 years |  |  |  |  |  |
PSL | PSL Promissory Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Extinguishment of Debt, Amount | $ 6,596,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Sanken |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Other accounts receivable from related party |  |  |  |  |  |  |  |  |  | 119,000 |  | 119,000 |  | 160,000
Sanken | Sanken Distribution Agreement, One-Time Sales Return |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Trade accounts receivable, net |  |  |  |  |  |  |  |  |  | $ 0 |  | $ 0 |  | $ 0
Sanken |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ownership percentage by majority shareholder |  |  |  |  |  |  |  |  |  | 32.50% |  | 32.50% |  |
Allegro Microsystems, Inc. | Polar Semiconductor, LLC |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ownership percentage by majority shareholder |  |  |  |  |  |  | 10.20% |  |  |  |  |  |  |

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