Note 2 - Earnings Per Share (Details Textual) - $ / shares |
12 Months Ended | ||
---|---|---|---|
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
|
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number | 29,324 | 31,949 | 46,451 |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Lower Range Limit | $ 17.55 | $ 17.55 | $ 17.55 |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Upper Range Limit | $ 37.48 | $ 40.24 | $ 40.24 |
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements | 11,357 | 9,154 | 7,871 |
Employee Stock Option [Member] | |||
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements | 29,324 | 27,250 | 28,282 |