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Debt and Finance Obligation - Schedule of Debt (Details) - USD ($) $ in Thousands	Apr. 30, 2017	Oct. 31, 2016	Apr. 30, 2016	Nov. 09, 2015
Debt Instrument [Line Items]
Capitalized lease obligations	$ 719	$ 660
Deferred finance costs	(1,527)	(1,408)
Total debt	87,807	81,770
Current portion of long-term debt and finance obligation	(14,564)	(5,010)
Long-term debt	73,243	76,760
Connecticut Development Authority Note [Member]
Debt Instrument [Line Items]
Long-term Line of Credit	2,470	2,589
Debt Instrument, Face Amount			$ 4,000
Connecticut Clean Energy Fund [Member]
Debt Instrument [Line Items]
Long-term Line of Credit	6,051	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	47,111	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	20,991	$ 20,521
New Britain Renewable Energy Member [Member]
Debt Instrument [Line Items]
Long-term Line of Credit	$ 1,992