Note 4 - Property and Equipment (Tables)
|12 Months Ended|
Dec. 31, 2017
|Property, Plant and Equipment [Table Text Block]||
Tabular disclosure of physical assets used in the normal conduct of business and not intended for resale. Includes, but is not limited to, balances by class of assets, depreciation and depletion expense and method used, including composite depreciation, and accumulated deprecation.
Reference 1: http://www.xbrl.org/2003/role/presentationRef