Commitments and Contingent Liabilities (Details Textual) - 9 months ended Nov. 26, 2016 CAD in Thousands, $ in Thousands	USD ($)	CAD	USD ($)
Line of Credit Facility [Line Items]
Company's backlog bonded by performance bonds			$ 113,200
Face value of performance bonds			327,500
Total value of letter of credit			23,500
Purchase obligations			141,729
Gross proceeds from new markets tax credit transaction	$ 6,000
Deferred costs on new market tax credit transaction	$ 900
Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Maximum borrowing capacity		CAD 4,000	$ 175,000