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Note 6 - Leases (Details Textual) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2020 USD ($) ft² | Dec. 31, 2019 USD ($) | Jun. 30, 2020
Operating Lease, Payments | $ | $ 1.6 | $ 2.0 |
HONG KONG |  |  |
Area of Land (Square Foot) | 7,300 |  |
Rolling Hills Estates [Member] |  |  |
Area of Land (Square Foot) | 4,900 |  |
Lessee, Operating Lease, Renewal Term (Year) |  |  | 5 years
Richmond, British Columbia [Member] |  |  |
Area of Land (Square Foot) | 1,600 |  |
Metuchen, New Jersey [Member] |  |  |
Area of Land (Square Foot) | 2,000 |  |
CHINA |  |  |
Lessee, Number of Branches | 8 |  |

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