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Note 17 - Commitments and Contingencies (Details Textual) $ in Millions |  |  |  | 1 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | ---
Aug. 27, 2018 USD ($) | Aug. 27, 2018 CNY (¥) | Jul. 09, 2018 CNY (¥) | Jun. 29, 2018 EUR (€) | Apr. 30, 2018 USD ($) | Apr. 30, 2018 CNY (¥) | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($) | Dec. 31, 2015 USD ($)
Purchase Commitment, Remaining Minimum Amount Committed |  |  |  |  |  |  | $ 42.5 | $ 58.9 |
Arezzo Revenue Agency [Member] |  |  |  |  |  |  |  |  |
Loss Contingency, Estimate of Possible Loss |  |  |  |  |  |  |  | 12.0 |
Claim by Setec Netzwerke AG [Member] |  |  |  |  |  |  |  |  |
Litigation Settlement, Amount Awarded to Other Party | € |  |  |  | € 75,000 |  |  |  |  |
Claim by DG Yu Shing Industrial Development Company Limited [Member] | Donugguan Transpower Electric Products Co., Ltd. [Member] |  |  |  |  |  |  |  |  |
Loss Contingency, Number of Defendants |  |  |  |  |  |  |  |  | 3
Loss Contingency, Damages Sought, Value |  |  |  |  |  |  |  |  | $ 3.2
Loss Contingency, Damages Awarded, Value |  |  |  |  | $ 3.2 | ¥ 20,133,174 |  |  |
Claim Against Jimmei Entities [Member] | Donugguan Transpower Electric Products Co., Ltd. [Member] |  |  |  |  |  |  |  |  |
Litigation Settlement, Amount Awarded from Other Party | $ 3.2 | ¥ 20,430,203 | ¥ 20,133,174 |  |  |  |  |  |
Capital Addition Purchase Commitments [Member] |  |  |  |  |  |  |  |  |
Long-term Purchase Commitment, Amount |  |  |  |  |  |  | $ 2.8 | $ 5.2 |

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