Annual report pursuant to Section 13 and 15(d)

Note 5 - Company's Stock Option Plans (Details)

v3.3.1.900
Note 5 - Company's Stock Option Plans (Details) - USD ($)
 12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Options outstanding, shares (in shares) 239,023 [1] 362,800
Options outstanding, weighted average exercise price (in dollars per share) $ 7.81 [1] $ 9.53
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross 12,000 71,800
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price $ 4.19 $ 4.70
Exercised, shares (in shares) (3,423) (2,577)
Exercised, weighted average exercise price (in dollars per share) $ 2.79 $ 2.79
Exercised, aggregate intrinsic value [2] $ 4,298 $ 3,705
Forfeited/Expired, shares (in shares) (29,400) (193,000)
Forfeited/Expired, weighted average exercise price (in dollars per share) $ 8.13  
Options outstanding, shares (in shares) [1] 218,200 239,023
Options outstanding, weighted average exercise price (in dollars per share) [1] $ 7.65 $ 7.81
Options outstanding, weighted average remaining contractual term [1] 4 years 292 days 4 years 328 days
Options outstanding , aggregate intrinsic value [1],[2] $ 14,676 $ 41,957
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number [1] 169,533 167,223
Options exercisable, weighted average exercise price (in dollars per share) [1] $ 8.47 $ 9.15
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term [1] 4 years 182 days 4 years 73 days
Options exercisable, aggregate intrinsic value [1],[2] $ 14,676 $ 31,037
Options vested and expected to be vested, shares (in shares) 212,333 230,223
Options vested and expected to be vested, weighted average exercise price (in dollars per share) $ 7.72 $ 7.92
Options vested and expected to be vested, weighted average remaining contractual term 4 years 292 days 4 years 328 days
Options vested and expected to be vested, aggregate intrinsic value [2] $ 14,676 $ 41,957
Forfeited/Expired, weighted average exercise price (in dollars per share)   $ 9.95
[1] Options with exercise prices ranging from $2.79 to $14.75
[2] The intrinsic value of a stock option is the amount by which the market value of the underlying stock exceeds the exercise price of the option.