Long-term debt - Summary of Long Term Debt (Detail) - USD ($) $ in Thousands	Mar. 25, 2017	Mar. 26, 2016
Debt Instrument [Line Items]
Long-term debt and Capital lease obligations	$ 33,335	$ 52,285
Long-term debt:
Long-term debt and Capital lease obligations	33,335	52,285
Current portion of long-term debt	2,810	5,634
Long-term debt	30,525	46,651
Term Loan from Investissement Quebec Prime Plus Seven Percent [Member]
Debt Instrument [Line Items]
Long-term debt	2,141	2,786
Term Loan from Investissement Quebec Prime Plus Five Point Five Percent [Member]
Debt Instrument [Line Items]
Long-term debt	779	2,355
Capital Leasing Arrangements [Member] \| Land and Building [Member]
Debt Instrument [Line Items]
Obligation under capital leases		9,141
Term Loan Facility [Member]
Debt Instrument [Line Items]
Long-term debt	26,952	32,186
Term Loan from Investissement Quebec Prime Plus Ten Percent [Member]
Debt Instrument [Line Items]
Long-term debt	1,061	1,383
Secured Debt [Member] \| Furniture and Equipment [Member]
Debt Instrument [Line Items]
Obligation under capital leases	902	1,719
Cash Contribution [Member] \| Montrovest BV [Member]
Debt Instrument [Line Items]
Long-term debt	$ 1,500	1,500
Term Loan Facility Repaid In May Two Thousand Sixteen [Member]
Debt Instrument [Line Items]
Long-term debt		$ 1,215

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

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Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

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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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