Note G - Stock-based Compensation (Details Textual) - USD ($) $ in Thousands		3 Months Ended
Jan. 01, 2019	Mar. 31, 2019	Mar. 31, 2018
Increase in Common Stock Reserved for Issuance	1,058,214
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period		0	1,307
Share-based Payment Arrangement, Expense		$ 1,290	$ 1,281
Performance Shares [Member]
Share-based Payment Arrangement, Expense		$ 0	$ 0
2014 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized		5,076,694
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Reserved for Issuance, Incremental Percentage of Capital Stock Outstanding		4.00%

Amount of increase in common stock reserved for issuance.

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+ References

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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

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Number of share options (or share units) exercised during the current period.

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