Long-term debt - Summary of Long Term Debt (Detail) - USD ($) $ in Thousands	Mar. 28, 2015	Mar. 29, 2014
Debt Instrument [Line Items]
Long-term debt and Capital lease obligations	$ 56,784	$ 54,750
Long-term debt and Capital lease obligations	56,784	54,750
Current portion of long-term debt	4,745	4,537
Long-term debt	52,039	50,213
Capital Leasing Arrangements [Member] \| Land and Building [Member]
Debt Instrument [Line Items]
Obligation under capital leases	10,211	12,151
Term Loan from Investissement Quebec Prime Plus Seven Percent [Member]
Debt Instrument [Line Items]
Long-term debt	3,643	4,519
Term Loan from Investissement Quebec Prime Plus Five Point Five Percent [Member]
Debt Instrument [Line Items]
Long-term debt	3,478	4,708
Term Loan Facility [Member]
Debt Instrument [Line Items]
Long-term debt	33,000	28,000
Secured Debt [Member] \| Furniture and Equipment [Member]
Debt Instrument [Line Items]
Obligation under capital leases	3,362	3,872
Cash Contribution [Member]
Debt Instrument [Line Items]
Long-term debt	1,500	$ 1,500
Term Loan from Investissement Quebec Prime Plus Ten Percent [Member]
Debt Instrument [Line Items]
Long-term debt	$ 1,590

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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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

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