Note 11 - Business Segment Information (Details) (USD $)	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012
Note 11 - Business Segment Information (Details) [Line Items]
Number of Operating Segments	2
Entity Wide Revenue, Major Customer, Number		4
Power And Energy Group [Member] | Utility-Scale Energy Storage System [Member]
Note 11 - Business Segment Information (Details) [Line Items]
Proceeds from Customers for Progress Payments (in Dollars)	$ 2,766,000
Power And Energy Group [Member]
Note 11 - Business Segment Information (Details) [Line Items]
Proceeds from Customers for Progress Payments (in Dollars)	$ 4,924,000
Minimum [Member]
Note 11 - Business Segment Information (Details) [Line Items]
Concentration Risk, Percentage	10.00%	10.00%