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Nature of the Business and Basis of Presentation - Additional Information (Details)					1 Months Ended	3 Months Ended	12 Months Ended
	Feb. 02, 2021 USD ($) shares	Nov. 02, 2020 USD ($) $ / shares shares	Oct. 14, 2020 USD ($)	Mar. 28, 2020 USD ($)	Oct. 31, 2017	Mar. 27, 2020 USD ($)	Mar. 25, 2022 USD ($) continent location	Mar. 26, 2021 USD ($)	Mar. 27, 2020 USD ($)
Noncash or Part Noncash Divestitures [Line Items]
Percentage of ownership interest sold					0.288
Number of locations | location							16
Number of continents on which entity operates | continent							4
Estimated offering costs							$ 1,790,000
Related party note receivable, less current portion							5,625,000	$ 0
Equity investment in related party							27,671,000	26,664,000
Income in earnings of equity investment							1,007,000	1,413,000	$ 0
Adjustments to additional paid in capital, capitalization changes								19,165,000
IPO
Noncash or Part Noncash Divestitures [Line Items]
Number of shares issued in transaction (in shares) | shares	0	28,750,000
Offering price (in dollars per share) | $ / shares		$ 14.00
Net proceeds	$ 0	$ 321,425,000
Underwriting discounts		20,125,000
Estimated offering costs		$ 8,450,000
IPO - Selling Shareholders
Noncash or Part Noncash Divestitures [Line Items]
Number of shares issued in transaction (in shares) | shares	19,332,852	3,750,000
COVID-19
Noncash or Part Noncash Divestitures [Line Items]
Proceeds from unsecured credit facilities						$ 43,000,000
Estimated cash benefit, CARES Act, qualified improvement property							12,800,000
Allegro Microsystems, Inc. | IPO
Noncash or Part Noncash Divestitures [Line Items]
Number of shares issued in transaction (in shares) | shares		25,000,000
Disposal Group, Disposed of by Sale, Not Discontinued Operations | PSL
Noncash or Part Noncash Divestitures [Line Items]
Noncash or part noncash divestiture, amount of consideration received				$ 42,700,000
Noncash or part noncash divestiture, amount of consideration transferred				$ 15,000,000
Equity method investment, ownership percentage				30.00%
Equity investment in related party				$ 25,250,000
Adjustments to additional paid in capital, capitalization changes								19,165,000
Adjustments to additional paid in capital, income tax benefit from noncash or part noncash divestiture								$ 1,552,000
Disposal Group, Disposed of by Sale, Not Discontinued Operations | PSL | Sanken
Noncash or Part Noncash Divestitures [Line Items]
Ownership percentage by majority shareholder				70.00%
Disposal Group, Disposed of by Sale, Not Discontinued Operations | PSL | PSL
Noncash or Part Noncash Divestitures [Line Items]
Related party debt				$ 66,377,000
Related party note receivable, less current portion				$ 51,377,000
Repayments of related party notes receivable			$ 51,377,000
Interest payable			762,000				$ 762,000
Interest paid			$ 762,000

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