ESPP maximum annual share replenishment.

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- Definition

ESPP maximum annual share replenishment percentage of prior year outstanding company common stock.

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Employee stock purchase plan weighted average purchase price of shares purchased.

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Number of ESPP shares available for future issuance.

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The reduction rate in the number of shares reserved under the option plan attributable to awards other than options or stock appreciation rights.

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Aggregate number of common shares reserved for future issuance.

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Unrecognized cost of unvested share-based compensation awards.

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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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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 highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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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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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross number of share options (or share units) granted during the period.

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No definition available.

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Number of options outstanding, including both vested and non-vested options.

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Price of a single share of a number of saleable stocks of a company.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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Purchase price of common stock expressed as a percentage of its fair value.

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Number of shares issued during the period as a result of an employee stock purchase plan.

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Amount of stock repurchase plan authorized.

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Period which shares may be purchased under a stock repurchase plan authorized by an entity's Board of Directors, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount remaining of a stock repurchase plan authorized.

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Total cost of shares repurchased divided by the total number of shares repurchased.

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Number of shares that have been repurchased during the period and are being held in treasury.

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Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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Note 4 - Stockholders' Equity (Details Textual) - USD ($) $ / shares in Units, $ in Millions			1 Months Ended	3 Months Ended		9 Months Ended		23 Months Ended
	May 31, 2017	Oct. 25, 2016	Jul. 31, 2001	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Dec. 31, 2017	Dec. 31, 2001
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period						30,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number, Ending Balance				1,045,000		1,045,000		1,045,000	1,045,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross				87,000		98,000
Share Price				$ 9.03		$ 9.03		$ 9.03
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value						$ 0.3
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value						$ 0.3
Stock Repurchase Program, Authorized Amount		$ 25.0
Stock Repurchase Program, Period in Force		2 years
Treasury Stock, Shares, Acquired				0		437,007		1,279,189
Treasury Stock Acquired, Average Cost Per Share								$ 14.59
Treasury Stock, Value, Acquired, Cost Method								$ 18.7
Stock Repurchase Program, Remaining Authorized Repurchase Amount				$ 25.0		$ 25.0		25.0
Employee Stock Option [Member]
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Total				1.1		$ 1.1		1.1
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition						3 years
Restricted Stock Units (RSUs) [Member]
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Total				$ 14.0		$ 14.0		$ 14.0
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition						2 years 73 days
Twenty Eleven Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	7,800,000
Share Based Compensation Arrangement By Share Based Payment Award Shares Reserved Decrease Rate	1.33
Common Stock, Capital Shares Reserved for Future Issuance				9,600,000		9,600,000		9,600,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant				4,000,000		4,000,000		4,000,000
Twenty Eleven Stock Incentive Plan [Member] \| Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period	10 years
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	4 years
Shares Previously Issued Under the 2001 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized										3,500,000
Two Thousand One Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period						500,000
Outside of the 2011, 2001 or IDS Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number, Ending Balance				0		0		0
Employee Stock Purchase Plan [Member]
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, Total				$ 1.7		$ 1.7		$ 1.7
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition						1 year 302 days
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Employee Subscription Rate			10.00%
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent			85.00%
ESPP Maximum Annual Share Replenishment			675,000
ESPP Maximum Annual Share Replenishment Percentage of Prior Year Outstanding Company Common Stock			2.00%
Stock Issued During Period, Shares, Employee Stock Purchase Plans				92,345	99,550	200,704	199,827
Employee Stock Purchase Plan Weighted Average Purchase Price of Shares Purchased				$ 8.925	$ 9.53	$ 9.12	$ 9.33
Number Of ESPP Shares Available For Future Issuance				4,700,000		4,700,000		4,700,000