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COMMITMENTS AND CONTINGENCIES (Details) $ in Millions |  |  | 6 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Jul. 09, 2018 CNY (¥) | Jun. 01, 2018 USD ($) | Jun. 30, 2018 USD ($) Defendant | Jun. 30, 2018 EUR (€) Defendant | Jun. 30, 2018 CNY (¥) Defendant | Dec. 31, 2015 Subsidiary
Dongguan Transpower [Member] |  |  |  |  |  |
Legal Proceedings [Abstract] |  |  |  |  |  |
Indemnification asset included in other current assets |  |  | $ 3.2 |  |  |
Arezzo Revenue Agency [Member] |  |  |  |  |  |
Legal Proceedings [Abstract] |  |  |  |  |  |
Estimated liability |  |  | $ 12.0 |  |  |
Setec [Member] |  |  |  |  |  |
Legal Proceedings [Abstract] |  |  |  |  |  |
Number of subsidiaries named in the lawsuit | Subsidiary |  |  |  |  |  | 3
Setec [Member] | Dongguan Transpower [Member] |  |  |  |  |  |
Legal Proceedings [Abstract] |  |  |  |  |  |
Amount paid in exchange for perpetual, worldwide royalty-free license to patent-in-suit | € |  |  |  | € 75,000 |  |
DG Yu Shing Industrial Development Company Limited [Member] | Dongguan Transpower [Member] |  |  |  |  |  |
Legal Proceedings [Abstract] |  |  |  |  |  |
Number of defendants | Defendant |  |  | 3 | 3 | 3 |
Damages sought |  |  | $ 3.2 |  |  |
Damages awarded | ¥ |  |  |  |  | ¥ 20,133,174 |
Jinmei Entities [Member] | Subsequent Event [Member] |  |  |  |  |  |
Legal Proceedings [Abstract] |  |  |  |  |  |
Damages received with incurred interest | ¥ | ¥ 20,133,174 |  |  |  |  |
Unipower, LLC [Member] |  |  |  |  |  |
Legal Proceedings [Abstract] |  |  |  |  |  |
Damages sought |  | $ 1.0 |  |  |  |

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