Note 12 - Interest and Other Income, Net - Interest and Other Income Components (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Interest income	$ 1,583	$ 1,346	$ 4,606	$ 3,938
Amortization of premium on available-for-sale securities	(314)	(490)	(1,122)	(1,494)
Gain on deferred compensation plan investments	717	636	949	1,902
Foreign currency exchange gain (loss)	700	(237)	915	(473)
Other	28		39
Total	$ 2,714	$ 1,255	$ 5,387	$ 3,873

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

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