ESPP maximum annual share replenishment.

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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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Amount of cost capitalized for award under share-based payment arrangement.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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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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Number of shares authorized for issuance under share-based payment arrangement.

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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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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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Note 7 - Employee Benefit Plans (Details Textual) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended		9 Months Ended
	Jul. 31, 2001	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018	Dec. 31, 2001
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period				4 years
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period				75,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number, Ending Balance		746,000		746,000		1,027,000
Share-based Payment Arrangement, Amount Capitalized				$ 244
Share Price		$ 13.07		$ 13.07
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value				$ 1,500
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value				100
Software Development [Member]
Share-based Payment Arrangement, Amount Capitalized				200
Share-based Payment Arrangement, Option [Member]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total		$ 700		$ 700
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition				2 years 292 days
Restricted Stock Units (RSUs) [Member]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total		$ 19,400		$ 19,400
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition				2 years 292 days
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period	10 years
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		85,000	92,000	172,000	200,000
Employee Stock Purchase Plan Weighted Average Purchase Price of Shares Purchased		$ 8.90	$ 8.93	$ 8.92	$ 9.12
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total		$ 900		$ 900
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition				1 year 146 days
Number Of ESPP Shares Available For Future Issuance		5,200,000		5,200,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number, Ending Balance		0		0
Twenty Eleven Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized		10,300,000		10,300,000
Share Based Compensation Arrangement By Share Based Payment Award Shares Reserved Decrease Rate				1.33
Common Stock, Capital Shares Reserved for Future Issuance		10,800,000		10,800,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant		3,500,000		3,500,000
Twenty Eleven Stock Incentive Plan [Member] \| Share-based Payment Arrangement, 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
IDS Plan [Member] \| Share-based Payment Arrangement, 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
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