Note 10 - Other Expense, Net - Interest and Other Income Components (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Interest income	$ 11,637	$ 9,327	$ 7,305
Amortization of premium on available-for-sale securities	(4,674)	(2,979)	(729)
Gain on deferred compensation plan investments	4,563	4,592	3,806
Foreign currency exchange loss	(727)	(1,364)	(310)
Other	(997)	884	486
Total	$ 9,802	$ 10,460	$ 10,558

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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