Note 3 - Summary of Significant Accounting Policies (Details Textual)		12 Months Ended
	Dec. 22, 2022 shares	Dec. 31, 2023 USD ($) shares	Dec. 31, 2022 USD ($) shares	Jan. 01, 2022 USD ($)	Dec. 31, 2021 USD ($)
Stockholders' Equity Note, Stock Split, Conversion Ratio	45
Common Stock, Shares Authorized | shares	350,000,000	350,000,000	350,000,000
Cash and Cash Equivalents, at Carrying Value		$ 2,000,000	$ 4,177,000
Inventory, Noncurrent		0	1,003,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Dividend Payments		0
Unrecognized Tax Benefits, Ending Balance		0	0
Equity, Including Portion Attributable to Noncontrolling Interest		(3,584,000)	3,323,000		$ 3,397,000
Retained Earnings [Member]
Equity, Including Portion Attributable to Noncontrolling Interest		(284,168,000)	(266,193,000)		(264,662,000)
Additional Paid-in Capital [Member]
Equity, Including Portion Attributable to Noncontrolling Interest		$ 282,383,000	270,377,000		268,459,000
Accounting Standards Update 2020-06 [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member]
Equity, Including Portion Attributable to Noncontrolling Interest					(942,000)
Accounting Standards Update 2020-06 [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member] | Convertible Debt [Member]
Debt Instrument, Unamortized Discount				$ 942,000
Accounting Standards Update 2020-06 [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member] | Retained Earnings [Member]
Equity, Including Portion Attributable to Noncontrolling Interest				9,739,000	9,739,000
Accounting Standards Update 2020-06 [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member] | Additional Paid-in Capital [Member]
Equity, Including Portion Attributable to Noncontrolling Interest				$ 10,681,000	$ (10,681,000)
Minimum [Member]
Finite-Lived Intangible Asset, Useful Life		3 years
Maximum [Member]
Finite-Lived Intangible Asset, Useful Life		10 years
INDIA
Cash and Cash Equivalents, at Carrying Value		$ 14,000	$ 47,000
CAR-TXpress [Member]
Subsidiary, Ownership Percentage, Noncontrolling Owner		20.00%
Subsidiary, Ownership Percentage, Parent		80.00%