Note 10 - Other Income, Net (Tables)

12 Months Ended

Dec. 31, 2020

Notes Tables

Schedule of Other Nonoperating Income (Expense) [Table Text Block]

	Year Ended December 31,
	2020			2019			2018
Interest income	$	9,327		$	7,305		$	6,321
Amortization of premium on available-for-sale securities		(2,979	)		(729	)		(1,353	)
Gain (loss) on deferred compensation plan investments		4,592			3,806			(1,022	)
Foreign currency exchange gain (loss)		(1,364	)		(310	)		953
Other		884			486			95
Total	$	10,460		$	10,558		$	4,994