Note 5 - Non-operating Income - Summary of Non-operating Income (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Equity in earnings of unconsolidated investments	$ 12,342	$ 9,744	$ 1,020
Dividends and net realized gains on sale of securities	8,390	7,840	7,417
Interest income	5,795	7,188	7,183
Gain on acquisitions of equity method investments	1,707	1,975	2,050
Total non-operating income	$ 28,234	$ 26,747	$ 17,670

The amount of dividends and other net realized gains and losses resulting from the sale of securities.

No definition available.

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The amount of gain (loss) recognized upon the acquisition of equity method investment.

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Amount of income (loss) for proportionate share of equity method investee's income (loss).

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The net amount of nonoperating interest income (expense).

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

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