Long-term debt - Summary of Long Term Debt (Parenthetical) (Detail) - USD ($)		12 Months Ended
Jul. 08, 2020	Mar. 27, 2021	Mar. 28, 2020
Debt Instrument [Line Items]
Net of deferred financing costs		$ 300,000	$ 400,000
Finance Lease Obligations [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt Instrument Interest Rate Stated Percentage Rate		2.20%	2.20%
Finance Lease Obligations [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt Instrument Interest Rate Stated Percentage Rate		3.90%	3.90%
Investissement Québec [Member]
Debt Instrument [Line Items]
Debt Instrument Interest Rate Stated Percentage Rate	3.14%	3.14%
Long-term debt	$ 10,000,000	$ 10,000,000
Repayment of debt term	60 months	60 months
Deferred financing costs		$ 44,000
Cash Contribution one [Member] \| Montel [Member]
Debt Instrument [Line Items]
Interest on Cash advances		11.00%	11.00%
Cash received from related party		$ 1,500,000	$ 1,500,000
Long-term debt		$ 1,887,000	$ 2,109,000
Cash Contribution Two [Member] \| Montel [Member]
Debt Instrument [Line Items]
Interest on Cash advances		11.00%	11.00%
Line of Credit Facility Repayment Date		Aug. 31, 2021	Aug. 31, 2021
Cash received from related party		$ 2,500,000	$ 2,500,000
Long-term debt		$ 1,573,000	$ 1,757,000
Term Loan Facility Repayable At October Two Thousand Twenty Two [Member] \| Term Loan From SLR Credit Solutions CDOR Plus Eight Point Two Five Percent [Member]
Debt Instrument [Line Items]
Debt Instrument Interest Rate Stated Percentage Rate		8.25%	8.25%
Net of deferred financing costs		$ 167,000	$ 272,000
Long-term debt		$ 12,333,000	$ 12,228,000

Deferred financing costs.

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- Definition

Interest Rate on Cash Advances

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- Definition

Line Of Credit Facility Repayment Date

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- Definition

Repayment of debt term.

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Contractual interest rate for funds borrowed, under the debt agreement.

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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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No definition available.

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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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- Definition

The cash inflow from a long-term borrowing made from related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth. Alternate caption: Proceeds from Advances from Affiliates.

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