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Debt and Finance Obligation - Schedule of Debt (Details) - USD ($) $ in Thousands	Jul. 31, 2017	Oct. 31, 2016	Nov. 09, 2015
Debt Instrument [Line Items]
Capitalized lease obligations	$ 738	$ 660
Deferred finance costs	(1,415)	(1,408)
Total debt	87,839	81,770
Current portion of long-term debt and finance obligation	(21,738)	(5,010)
Long-term debt	66,101	76,760
Connecticut Development Authority Note [Member]
Debt Instrument [Line Items]
Long-term Line of Credit	2,410	2,589
Debt Instrument, Face Amount	4,000
Connecticut Clean Energy Fund [Member]
Debt Instrument [Line Items]
Long-term Line of Credit	6,052	6,050
NRG Energy, Inc. [Member]
Debt Instrument [Line Items]
Long-term Line of Credit		1,755
PNC Energy Capital, LLC [Member]
Debt Instrument [Line Items]
Long-term Line of Credit	46,980	41,603
CT Department of Economic & Community Development [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	21,229	$ 20,521
New Britain Renewable Energy Member [Member]
Debt Instrument [Line Items]
Long-term Line of Credit	$ 1,845