Note 12 - Stock-based Compensation (Details)	12 Months Ended
Dec. 31, 2015 USD ($) shares	Dec. 31, 2014 USD ($) shares
Note 12 - Stock-based Compensation (Details) [Line Items]
Number of Share Based Compensation Plans	2
Allocated Share-based Compensation Expense \| $	$ 68,705	$ 59,798
Employee Service Share-based Compensation, Tax Benefit Realized from Exercise of Stock Options \| $	$ 0	$ 0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period	0	0
1997 Stock Option Plan [Member]
Note 12 - Stock-based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	27,750
2008 Plan [Member]
Note 12 - Stock-based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	138,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	806,100
Restricted Stock [Member] \| 2008 Plan [Member]
Note 12 - Stock-based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number	10,425
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period		4 years
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	0	13,900
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized \| $	$ 60,522	$ 89,574
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition	2 years
Employee Stock Option [Member] \| 2008 Plan [Member]
Note 12 - Stock-based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period	10 years
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized \| $	$ 137,812	$ 112,764
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition	4 years
Minimum [Member] \| Employee Stock Option [Member] \| 2008 Plan [Member]
Note 12 - Stock-based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	1 year
Maximum [Member] \| Employee Stock Option [Member] \| 2008 Plan [Member]
Note 12 - Stock-based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	5 years

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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