Discontinued Operations-Schneider Power - Additional Information (Detail)			0 Months Ended		0 Months Ended						1 Months Ended			12 Months Ended			0 Months Ended
	Mar. 31, 2013 USD ($)	Dec. 31, 2012	Mar. 19, 2013 Amendment of Debt Agreement [Member] CAD	Mar. 19, 2013 Amendment of Debt Agreement [Member] Term Loan [Member]	Mar. 19, 2013 March 31, 2013 [Member] Amendment of Debt Agreement [Member] CAD	Mar. 19, 2013 July 31,2013 [Member] Amendment of Debt Agreement [Member] CAD	Mar. 19, 2013 Januay 31, 2014 [Member] Amendment of Debt Agreement [Member] CAD	Mar. 19, 2013 July 31,2018 [Member] Amendment of Debt Agreement [Member] CAD	Mar. 19, 2013 July 31,2022 [Member] Amendment of Debt Agreement [Member] CAD	Mar. 19, 2013 Jan 31, 2023 [Member] Amendment of Debt Agreement [Member] CAD	Apr. 20, 2012 Zephyr Farms Limited CAD	Mar. 31, 2013 Zephyr Farms Limited USD ($) MW	Mar. 31, 2013 Zephyr Farms Limited CAD	Dec. 31, 2012 Providence Bay Wind Farm CAD	Mar. 31, 2013 Providence Bay Wind Farm USD ($) MW	Apr. 16, 2010 Providence Bay Wind Farm CAD	May 14, 2013 Subsequent Event Providence Bay Wind Farm CAD
Discontinued Operations [Line Items]
Capacity of plant												10.0	10.0		1.6
Proceeds from sale of businesses																	406,000
Project debt assumed by buyer																	1,066,826
Bank term loan, principal amount											23,200,000	22,700,000
Term loan interest payment frequency											semi-annual
Bank Term Loan, interest rate			6.50%	6.50%							6.50%
Term of loan				10 years
Bank Term Loan, monthly fixed cash payment			1,050,000											12,899
Final payment in year ten			9,600,000
Required principal balloon payment in year five			5,300,000
Debt Instrument, Interest Payment Due Post Agreement Amendment					100,000	1,300,000
Debt Instrument, Periodic Payment Post Agreement Amendment							1,100,000
Debt Instrument, Principal Balloon Payment Post Agreement Amendment								0	4,900,000
Debt Instrument, Final Payment Post Agreement Amendment										5,100,000
Unamortized debt premium												900,000
Total amount of debt	13,250,519												24,500,000
Accrued Interest on debt												900,000
Acquisition, liabilities assumed																1,500,000
Conversion rate of one CAD to one Dollar	0.982	1.005
Bank term loan															1,100,000
Bank Term Loan, interest rate														0.060
Bank term loan, maturity date														Apr. 10, 2017
Bank Term Loan, amount paid on maturity														667,422