Note 6 - Non-operating Income - Summary of Non-operating Income (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Dividends and net realized gains and losses on sales of securities	$ 1,304	$ 1,915	$ 3,057	$ 3,877
Interest income	1,207	1,276	2,199	2,663
Equity in earnings of unconsolidated investments	10	2,395	464	5,306
Total non-operating income	$ 2,521	$ 5,586	$ 5,720	$ 11,846

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

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