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Debt - Schedule of Debt (Details) - USD ($) $ in Thousands	Oct. 31, 2018	Mar. 28, 2018	Oct. 31, 2017
Debt Instrument [Line Items]
Capitalized lease obligations	$ 341		$ 632
Deferred finance costs	(1,311)		(1,344)
Total debt	87,878		87,791
Current portion of long-term debt	(17,596)		(28,281)
Long-term debt	70,282		59,510
Hercules Capital, Inc. [Member]
Debt Instrument [Line Items]
Long-term Line of Credit	25,343	$ 11,900	21,468
State of Connecticut Loan [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	10,000		10,000
Finance Obligation for Sale-Lease Back Transactions [Member]
Debt Instrument [Line Items]
Long-term Line of Credit	46,062		46,937
Connecticut Green Bank Note [Member]
Debt Instrument [Line Items]
Long-term Line of Credit	6,052		6,052
Connecticut Development Authority Note [Member]
Debt Instrument [Line Items]
Long-term Line of Credit	284		2,349
New Britain Renewable Energy Member [Member]
Debt Instrument [Line Items]
Long-term Line of Credit	$ 1,107		$ 1,697