Note 18 - Concentration of Risk in Customer and Supplier Relationships (Details) - Percentages of Sales to Largest Customers - Sales Revenue, Goods, Net [Member] - Customer Concentration Risk [Member] |
9 Months Ended | 12 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2015 |
Sep. 30, 2014 |
Dec. 31, 2014 |
Dec. 31, 2013 |
|
| Smart Energy Today [Member] | ||||
| Concentration Risk [Line Items] | ||||
| Percentage of sales | 30.40% | 13.50% | 13.30% | 13.50% |
| WDC Solar, Inc. [Member] | ||||
| Concentration Risk [Line Items] | ||||
| Percentage of sales | 0.00% | 14.70% | 12.00% | 14.70% |
| JCF Wholesale [Member] | ||||
| Concentration Risk [Line Items] | ||||
| Percentage of sales | 0.00% | 10.60% | 8.70% | 10.60% |
| Lowe's Companies, Inc. [Member] | ||||
| Concentration Risk [Line Items] | ||||
| Percentage of sales | 5.90% | 6.90% | ||
| Sustainable Environmental Enterprises [Member] | ||||
| Concentration Risk [Line Items] | ||||
| Percentage of sales | 1.30% | 52.80% | ||