Revenue from Contracts with Customers - Net Sales by Core End Market and Application (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 26, 2025	Dec. 27, 2024	Dec. 26, 2025	Dec. 27, 2024
Disaggregation of Revenue [Line Items]
Total net sales	$ 229,210	$ 177,872	$ 646,909	$ 532,182
Automotive
Disaggregation of Revenue [Line Items]
Total net sales	164,543	128,637	464,652	395,711
Industrial and Other
Disaggregation of Revenue [Line Items]
Total net sales	$ 64,667	$ 49,235	$ 182,257	$ 136,471

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details

ALLEGRO MICROSYSTEMS, INC. 10-Q