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Related Party Transactions (Details) - USD ($)				3 Months Ended		6 Months Ended
Related Party Transactions (Details) - USD ($)	Mar. 31, 2023	Jan. 26, 2023	Dec. 02, 2021	Sep. 29, 2023	Sep. 23, 2022	Sep. 29, 2023	Sep. 23, 2022	Oct. 02, 2023	Sep. 11, 2023	Jul. 01, 2022
Related Party Transaction [Line Items]
Total net sales				$ 275,509,000	$ 237,666,000	$ 553,802,000	$ 455,419,000
Trade accounts receivable, net	$ 111,290,000			118,947,000		118,947,000
Periodic payment						2,004,000
Interest income						129,000
PSL
Related Party Transaction [Line Items]
Purchases from related party				14,630,000	14,479,000	30,732,000	29,150,000
Amounts due to related party	4,682,000			3,041,000		3,041,000
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				10,313,000		10,313,000
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									$ 4,000,000
Interest rate									12.50%
Majority Shareholder
Related Party Transaction [Line Items]
Trade accounts receivable, net	13,253,000			575,000		575,000
Other accounts receivable from related party	241,000			85,000		85,000
Amounts due to related party	0			0		0
Majority Shareholder \| Sanken Distribution Agreement, One-Time Sales Return
Related Party Transaction [Line Items]
Trade accounts receivable, net	4,200,000			1,943,000		1,943,000
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
Subsequent Event \| Crocus Technologies \| Initial Crocus Loan \| Loans Payable
Related Party Transaction [Line Items]
Principal amount								$ 3,000,000
Related Party Revenue \| Majority Shareholder
Related Party Transaction [Line Items]
Total net sales				$ 3,579,000	$ 45,026,000	$ 3,579,000	$ 86,735,000
Sanken
Related Party Transaction [Line Items]
Ownership percentage by majority shareholder				51.20%		51.20%
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%