Segment information (Details 1) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Revenue	$ 15,383	$ 17,940	$ 14,949
Geographical analysis of long-lived assets	159	168
The PRC
Revenue	6,398	7,125	5,878
Geographical analysis of long-lived assets	154	162
Hong Kong
Revenue	6,745	9,879	7,174
Geographical analysis of long-lived assets	5	6
Others
Revenue	$ 2,240	$ 936	$ 1,897

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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+ Details