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COMMITMENTS AND CONTINGENCIES (Details) $ in Millions			6 Months Ended			12 Months Ended
COMMITMENTS AND CONTINGENCIES (Details) $ in Millions	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