Note 13 - Interest and Other Income, Net - Interest and Other Income Components (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Interest income	$ 1,661	$ 1,563	$ 3,357	$ 3,024
Amortization of premium on available-for-sale securities	(95)	(374)	(216)	(808)
Gain on deferred compensation plan investments	620	419	2,555	233
Foreign currency exchange gain (loss)	73	614	(128)	214
Other	(30)	10	1	10
Total	$ 2,229	$ 2,232	$ 5,569	$ 2,673

Gains or losses on deferred compensation plan investments.

No definition available.

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- Definition

The sum of the periodic adjustments of the differences between securities' face values and purchase prices that are charged against earnings. This is called accretion if the security was purchased at a discount and amortization if it was purchased at premium. As a noncash item, this element is an adjustment to net income when calculating cash provided by or used in operations using the indirect method.

+ References

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- Definition

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

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- Definition

The net amount of nonoperating interest income (expense).

+ References

No definition available.

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- Definition

The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business).

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Amount of income (expense) related to nonoperating activities, classified as other.

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