Note 5 - Stock Option Plans (Tables)
|9 Months Ended|
Sep. 30, 2016
|Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block]||
Tabular disclosure of the number and weighted-average exercise prices (or conversion ratios) for share options (or share units) that were outstanding at the beginning and end of the year, vested and expected to vest, exercisable or convertible at the end of the year, and the number of share options or share units that were granted, exercised or converted, forfeited, and expired during the year.
Reference 1: http://www.xbrl.org/2003/role/presentationRef