Note 10 - Equity, Share-based Compensation and Warrants - Stockholders Equity (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Balance (in shares)	51,589,674
Balance	$ 18,495	$ 23,420
Common stock awards under equity incentive plans	241	250
Common stock issued to vendor	5	3
Net income (loss)	$ (1,516)	591
Other		(3)
Balance (in shares)	51,820,425
Balance	$ 17,225	24,261
Preferred Stock [Member]
Balance	75	112
Common stock awards under equity incentive plans	0	0
Common stock issued to vendor	0	0
Net income (loss)	0	0
Other
Balance	$ 75	$ 112
Preferred Stock [Member] | Series G Preferred Stock [Member]
Balance (in shares)	150	225
Common stock awards under equity incentive plans (in shares)	0	0
Common stock issued to vendor (in shares)	0	0
Balance (in shares)	150	225
Common Stock [Member]
Balance (in shares)	51,589,674	45,238,087
Balance	$ 326,279	$ 322,218
Common stock awards under equity incentive plans (in shares)	224,751	29,943
Common stock awards under equity incentive plans	$ 241	$ 250
Common stock issued to vendor (in shares)	6,000	6,000
Common stock issued to vendor	$ 5	$ 3
Net income (loss)	$ 0	0
Other		$ (3)
Balance (in shares)	51,820,425	45,274,030
Balance	$ 326,525	$ 322,468
Retained Earnings [Member]
Balance	(307,859)	(298,910)
Common stock awards under equity incentive plans	0	0
Common stock issued to vendor	0	0
Net income (loss)	(1,516)	591
Other
Balance	$ (309,375)	$ (298,319)