Note 9 - Assets Held for Sale (Detail) (USD $)			1 Months Ended	3 Months Ended
	Mar. 31, 2013	Dec. 31, 2012	May 31, 2012 Solar Facility [Member]	Jun. 30, 2011 Solar Facility [Member]	Jun. 30, 2012 Solar Facility [Member]	Dec. 31, 2011 Solar Facility [Member]	Dec. 31, 2010 Solar Facility [Member]	Jan. 02, 2010 Solar Facility [Member]	Dec. 31, 2011 SEF [Member]
Assets Held-for-sale, Current	$ 0	$ 0				$ 6,300,000	$ 6,700,000	$ 10,000,000	$ 5,500,000
Long Lived Assets Held-for-sale, Impairment Charge							3,300,000
Asset Impairment Charges			700,000	400,000
Liabilities of Assets Held-for-sale			4,200,000
Long Lived Assets Held-for-sale, Proceeds from Sale					$ 1,500,000