Note O - Accumulated Other Comprehensive Income (Loss) - Reclassifications Out of Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Gains on available-for-sale marketable securities		$ 343	$ 416	$ 1,535	$ 1,129
Provision for income taxes		(90)	(335)	(152)	(947)
Net Loss		(1,891)	484	(5,434)	(1,103)
Research and development	[1]	8,122	9,244	26,931	26,725
Sales and marketing	[2]	4,117	4,311	13,563	13,180
General and administrative	[3]	2,864	2,388	7,839	7,617
Research and development	[1]	8,122	9,244	26,931	26,725
Provision for income taxes		(90)	$ (335)	(152)	$ (947)
Reclassification out of Accumulated Other Comprehensive Income [Member]
Net Loss		(21)		(73)
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Parent [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Gains on available-for-sale marketable securities		(27)		(39)
Provision for income taxes		0		0
Net Loss		(27)		(39)
Provision for income taxes		0		0
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Research and development		3		9
Research and development		3		9
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Provision for income taxes				0
Net Loss				(52)
Research and development				(41)
Sales and marketing				(4)
General and administrative				(7)
Research and development				(41)
Provision for income taxes				0
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Sales and marketing		3		9
General and administrative		6		18
Net Loss		$ 6		$ 18

[1] Includes equity-based compensation expense in the amount of $946 and $677 for the three months ended September 30, 2020 and 2019, respectively; and $2,523 and $2,202 for the nine months ended September 30, 2020 and 2019, respectively.

[2] Includes equity-based compensation expense in the amount of $646 and $442 for the three months ended September 30, 2020 and 2019, respectively; and $1,821 and $1,318 for the nine months ended September 30, 2020 and 2019, respectively.

[3] Includes equity-based compensation expense in the amount of $699 and $645 for the three months ended September 30, 2020and 2019, respectively; and $1,811 and $1,972 for the nine months ended September 30, 2020 and 2019, respectively.