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Debt and Financing Obligation - Schedule of Debt (Details) - USD ($) $ in Thousands	Jul. 31, 2019	Oct. 31, 2018	Nov. 30, 2015
Debt Instrument [Line Items]
Long-term Line of Credit	$ 1,800
Capitalized lease obligations	195	$ 341
Deferred finance costs	(2,621)	(1,311)
Total debt and financing obligations	121,238	87,878
Current portion of long-term debt and financing obligations	(43,416)	(17,596)
Long-term debt and financing obligations	77,822	70,282
Connecticut Development Authority Note [Member]
Debt Instrument [Line Items]
Long-term Line of Credit		284
Connecticut Green Bank Loans [Member]
Debt Instrument [Line Items]
Long-term Line of Credit	7,719	6,052
Finance Obligation for Sale-Lease Back Transactions [Member]
Debt Instrument [Line Items]
Long-term Line of Credit	45,247	46,062
State of Connecticut Loan [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	10,000	10,000	$ 10,000
Hercules Capital, Inc. [Member]
Debt Instrument [Line Items]
Long-term Line of Credit	7,426	25,343
New Britain Renewable Energy [Member]
Debt Instrument [Line Items]
Long-term Line of Credit	644	$ 1,107
NRG Construction Loan Facility [Member]
Debt Instrument [Line Items]
Long-term Line of Credit	5,750
Generate Lending Construction Loan Agreement [Member]
Debt Instrument [Line Items]
Long-term Line of Credit	10,000
Enhanced Capital Term Loan and Security Agreement [Member]
Debt Instrument [Line Items]
Long-term Line of Credit	1,500
Liberty Bank Term Loan Agreement [Member]
Debt Instrument [Line Items]
Long-term Line of Credit	12,153
Fifth Third Bank Term Loan Agreement [Member]
Debt Instrument [Line Items]
Long-term Line of Credit	12,153
Fifth Third Bank Construction Loan Agreement [Member]
Debt Instrument [Line Items]
Long-term Line of Credit	$ 11,072