Debt and Leases (Details) (USD $)	3 Months Ended	9 Months Ended			9 Months Ended			9 Months Ended						9 Months Ended
	Jul. 31, 2014	Jul. 31, 2014	Oct. 31, 2013	Jun. 25, 2013	Jul. 31, 2014 NRG Energy [Member]	Jul. 31, 2014 NRG Energy, Inc. [Member]	Jun. 25, 2013 Convertible Debt [Member]	Jul. 31, 2014 Connecticut Development Authority Note [Member]	Oct. 31, 2013 Connecticut Development Authority Note [Member]	Mar. 05, 2013 Connecticut Clean Energy Fund [Member]	Jul. 31, 2014 Connecticut Clean Energy and Finance Investment Authority [Member]	Oct. 31, 2013 Connecticut Clean Energy and Finance Investment Authority [Member]	Mar. 05, 2013 Connecticut Clean Energy and Finance Investment Authority [Member]	Jul. 31, 2014 Parent [Member]	Jul. 31, 2014 London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Amount Outstanding	$ 945,000	$ 945,000	$ 6,500,000					$ 3,086,000	$ 3,246,000		$ 6,052,000	$ 5,744,000
Senior Unsecured Convertible Notes	0	0	38,000,000	38,000,000
Capital Lease Obligations	713,000	713,000	497,000
Long-term Debt, Gross	10,796,000	10,796,000	53,987,000
Debt Instrument, Unamortized Discount	0	0	(3,106,000)
Long-term Debt	10,796,000	10,796,000	50,881,000
Long-term Debt, Current Maturities	(1,404,000)	(1,404,000)	(6,931,000)
Long-term Debt, Excluding Current Maturities	9,392,000	9,392,000	43,950,000
Line of Credit Facility, Maximum Borrowing Capacity	4,000,000	4,000,000				40,000,000				5,900,000
Long-term Debt, Percentage Bearing Variable Interest, Percentage Rate															1.50%
Debt Instrument, Term								10 years
Debt Instrument, Interest Rate, Stated Percentage							8.00%	5.00%					5.00%
embedded derivative cash payment	300,000
Embedded Derivative, Fair Value of Embedded Derivative Liability	0	0	4,700,000
Stock Issued During Period, Shares, Conversion of Convertible Securities, Debt Obligation		5,514,272
Stock Issued During Period, Shares, Conversion of Convertible Securities		24,516,141
Stock Issued During Period, Value, Other		12,883,000												12,883,000
Embedded Derivative, Loss on Embedded Derivative	8,700,000
Embedded Derivative, No Longer Bifurcated, Amount Reclassified to Stockholders' Equity	4,600,000
Debt Conversion, Original Debt, Amount	38,000,000
Debt Instrument, Face Amount								4,000,000
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Maximum					8.50%
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Minimum						8.00%
Collateralized Agreements								$ 4,000,000