Note 13 - Interest and Other Income, Net - Interest and Other Income Components (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Interest income	$ 1,696	$ 1,460
Amortization of premium on available-for-sale securities	(121)	(435)
Gain (loss) on deferred compensation plan investments	1,935	(186)
Foreign currency exchange loss	(201)	(399)
Other	32
Total	$ 3,341	$ 440

Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

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