Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Number of shares distributed to participants who purchase the required amount on the open market.

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The amount of the remaining liabilities were reversed associated the modification of the plan.

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Shares matched.

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Note 8 - Equity Plans (Details Textual) - USD ($)				3 Months Ended	6 Months Ended	9 Months Ended	12 Months Ended
Note 8 - Equity Plans (Details Textual) - USD ($)	Mar. 13, 2017	Jul. 01, 2016	May 01, 2016	Sep. 30, 2016	Jun. 30, 2016	Sep. 30, 2017	Dec. 31, 2016	Mar. 31, 2017
Senior Management Compensation Program [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Minimum Number of Shares Per Employee					750
Share-based Compensation Arrangement by Share-based Payment Award, Matching Purchase Requirement					500
Share-based Compensation Arrangement by Share-based Payment Award, Award Match					250
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period						73,021
Restricted Stock Units (RSUs) [Member] \| Senior Management Stock Incentive Program [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period		5 years
Share-based Compensation Arrangement by Share-based Payment Award, Percentage of Participant's Base Salary		10.00%
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Amount Per Employee		$ 17,500
Restricted Stock Units (RSUs) [Member] \| Senior Management Compensation Program [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Plan Modification, Remaining Liability Reversed							$ 1,000,000
Restricted Stock Units (RSUs) [Member] \| Senior Management Compensation Program [Member] \| Five Year Anniversary [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Vested					$ 25,000
Restricted Stock Units (RSUs) [Member] \| Senior Management Compensation Program [Member] \| Ten Year Anniversary [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Vested					50,000
Restricted Stock Units (RSUs) [Member] \| Senior Management Compensation Program [Member] \| Fifteen Year Anniversary [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Vested					75,000
Restricted Stock Units (RSUs) [Member] \| Senior Management Compensation Program [Member] \| Twenty Five Year Anniversary [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Vested					100,000
Restricted Stock Units (RSUs) [Member] \| Senior Management Compensation Program [Member] \| Twenty Year Anniversary [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Vested					$ 100,000
Restricted Stock Units (RSUs) [Member] \| Non-Employee Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	3,501		3,094
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	1 year		1 year
Restricted Stock Units (RSUs) [Member] \| Executive Vice President and Chief Operating Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period				10,573
Match [Member] \| Senior Management Compensation Program [Member]
Shares Matched					2,500
Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant						1,000,000
Share Price			$ 22.62					$ 19.99