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Related Party Transactions (Details) - USD ($)					12 Months Ended
Related Party Transactions (Details) - USD ($)	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%