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Note 6 - Equity - Summary of Restricted Awards Activity (Details)								3 Months Ended			6 Months Ended
	Jun. 21, 2023 USD ($) shares	Jun. 15, 2023 $ / shares	Mar. 15, 2023 USD ($) $ / shares	Dec. 08, 2022 $ / shares	Jun. 15, 2022 $ / shares	Mar. 15, 2022 $ / shares	Feb. 18, 2022 USD ($)	Jun. 30, 2023 USD ($) $ / shares shares	Mar. 31, 2023 USD ($) $ / shares shares	Jun. 30, 2022 USD ($)	Jun. 30, 2023 USD ($) $ / shares shares	Jun. 30, 2022 USD ($)	May 15, 2023 USD ($)	Dec. 31, 2022 USD ($)	May 15, 2022 USD ($)
Compensation costs \| $								$ 3,600,000		$ 2,300,000	$ 6,500,000	$ 4,200,000
Distribution ratio for outstanding award	0.2
Changes in fair value \| $	$ 0
Incremental compensation costs associated with modifications \| $	$ 0
Dividend declared \| $ / shares				$ 0.125
Dividend accrued not paid \| $							$ 2,500,000		$ 354,000
Dividend payable \| $			$ 5,600,000				$ 5,000,000.0	$ 504,000			504,000		$ 5,600,000	$ 5,500,000	$ 5,000,000.0
Dividends paid \| $ / shares		$ 0.125	$ 0.1250		$ 0.11	$ 0.11
Payment of dividends \| $											$ 11,100,000	$ 10,000,000.0
Per share amount of a dividend declared \| $ / shares								$ 0			$ 0
Class B Common Stock
Number of shares issued	473,707
Restricted Stock
Fair value of awards \| $									$ 2,500,000
Vesting period									3 years
Restricted Stock \| Class B Common Stock
Outstanding, shares (in shares)								648,000			648,000
Shares in restricted stock	680,718
Restricted Stock Units
Granted, shares (in shares)									518,348
Granted, Weighted average grant date fair value (in dollars per share) \| $ / shares									$ 10.61
Fair value of awards \| $									$ 5,500,000
Vesting period									3 years
Delivery Period									30 days
Shares delivered per unit awarded									1
Restricted Stock Units \| Class B Common Stock
Granted, shares (in shares)	136,819
Performance Stock Units
Vesting period									3 years
Delivery Period									30 days
Performance Stock Units \| Class B Common Stock
Granted, shares (in shares)	153,404
Employee Stock Option [Member] \| Class B Common Stock
Options granted	183,484
Executives and Employees \| Restricted Stock
Granted, shares (in shares)									296,115
Granted, Weighted average grant date fair value (in dollars per share) \| $ / shares									$ 10.61
Executives and Employees \| Performance Stock Units
Granted, shares (in shares)									518,348
Granted, Weighted average grant date fair value (in dollars per share) \| $ / shares									$ 18.09
Fair value of awards \| $									$ 9,400,000
Vesting period									3 years
Shares delivered per unit awarded									1
Executives and Employees \| Performance Stock Units \| Minimum
Potential earnings (as a percentage)									0.00%
Executives and Employees \| Performance Stock Units \| Maximum
Potential earnings (as a percentage)									200.00%
Executives and Employees \| Performance Stock Units Granted in 2022
Granted, shares (in shares)									248,706
Fair value of awards \| $											$ 1,200,000
Directors \| Restricted Stock
Fair value of awards \| $									$ 600,000