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Debt and Financing Obligation - Schedule of Debt (Details) - USD ($)	Apr. 30, 2019	Dec. 13, 2018	Oct. 31, 2018	Nov. 30, 2015
Debt Instrument [Line Items]
Capitalized lease obligations	$ 249,000		$ 341,000
Deferred finance costs	(1,517,000)		(1,311,000)
Total debt and financing obligations	112,993,000		87,878,000
Current portion of long-term debt and financing obligations	(54,815,000)		(17,596,000)
Long-term debt and financing obligations	58,178,000		70,282,000
Connecticut Development Authority Note [Member]
Debt Instrument [Line Items]
Long-term Line of Credit			284,000
Connecticut Green Bank Note [Member]
Debt Instrument [Line Items]
Long-term Line of Credit	6,051,000		6,052,000
Finance Obligation for Sale-Lease Back Transactions [Member]
Debt Instrument [Line Items]
Long-term Line of Credit	45,284,000		46,062,000
State of Connecticut Loan [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	10,000,000		10,000,000	$ 10,000,000
Hercules Capital, Inc. [Member]
Debt Instrument [Line Items]
Long-term Line of Credit	23,812,000		25,343,000
New Britain Renewable Energy [Member]
Debt Instrument [Line Items]
Long-term Line of Credit	792,000		$ 1,107,000
NRG Energy [Member]
Debt Instrument [Line Items]
Long-term Line of Credit	5,750,000	$ 0
Generate Lending Construction Loan Agreement [Member]
Debt Instrument [Line Items]
Long-term Line of Credit	10,000,000
Enhanced Capital Loan and Security Agreement [Member]
Debt Instrument [Line Items]
Long-term Line of Credit	1,500,000
Fifth Third Bank Loan Agreement [Member]
Debt Instrument [Line Items]
Long-term Line of Credit	$ 11,072,000