Note 4 - Stock-Based Compensation - Schedule of Unvested Restricted Stock Activity (Details) - Restricted Stock [Member] - $ / shares shares in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021		Dec. 31, 2020
Balance (in shares)	196	360		416
Balance, weighted average grant date fair value (in dollars per share)	$ 32.06	$ 34.90		$ 28.20
Granted (in shares)		54		255
Granted, weighted average grant date fair value (in dollars per share)		$ 18.36		$ 40.53
Vested (in shares)		(187)	[1]	(246)
Vested, weighted average grant date fair value (in dollars per share)		$ 32.72	[1]	$ 29.76
Forfeited (in shares)		(31)	[1]	(65)
Forfeited, weighted average grant date fair value (in dollars per share)		$ 36.90	[1]	$ 33.64

[1] Includes the impact of the modification of 21 PRSUs which were cancelled and reissued at a grant date fair value of $28.93.