Note 4 - China Joint Venture (Details Textual) - USD ($)	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2019
Corporate Joint Venture [Member]
Controlling Interest, Required Capital Contribution		$ 408,000	$ 357,000
Controlling Interest, Increase From Capital Contributions	$ 0	$ 153,000
China JV Partner [Member]
Subsidiary, Ownership Percentage, Noncontrolling Owner			51.00%

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant