Note 9 - Other Income (Expense) - Schedule of Other Income (Expense) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Jun. 20, 2021
Interest income	$ 424	$ 9	$ 443	$ 24
Interest expense	0	(111)	0	(253)
Realized gain on disposal of equipment	69	0	70	44	$ 44
Total other income (expense)	$ 493	$ (102)	$ 513	$ (185)

Amount of gain (loss) on sale or disposal of property, plant and equipment assets, including oil and gas property and timber property.

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Amount of the cost of borrowed funds accounted for as interest expense.

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Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.

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

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