Number of subsidiaries named in the lawsuit.

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Refers to outstanding purchase orders related to capital expenditures.

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Refers to outstanding purchase orders related to raw materials.

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Amount paid in exchange for a perpetual, worldwide royalty-free license to the patent-in-suit and all its counterparts.

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Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

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Amount awarded from other party in judgment or settlement of litigation.

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Amount of damages awarded to the plaintiff in the legal matter.

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The value (monetary amount) of the award the plaintiff seeks in the legal matter.

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Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

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Number of defendants named in a legal action.

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Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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No definition available.

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COMMITMENTS AND CONTINGENCIES (Details) $ in Thousands				12 Months Ended
COMMITMENTS AND CONTINGENCIES (Details) $ in Thousands	Aug. 27, 2018 USD ($)	Aug. 27, 2018 CNY (¥)	Jul. 09, 2018 CNY (¥)	Dec. 31, 2018 USD ($) Defendant	Dec. 31, 2018 EUR (€) Defendant	Dec. 31, 2018 CNY (¥) Defendant	Dec. 31, 2017 USD ($)	Dec. 31, 2015 Subsidiary
Future minimum lease payments for operating leases [Abstract]
2019				$ 7,363
2020				6,017
2021				4,967
2022				3,338
2023				1,194
Thereafter				442
Total future minimum lease payments for operating leases				23,321
Rent expense for leases				8,000			$ 8,200
Other commitments [Abstract]
Outstanding purchase orders related to raw materials				58,900			45,400
Outstanding purchase orders related to capital expenditures				5,200			$ 3,000
Dongguan Transpower [Member]
Loss Contingency, Estimate [Abstract]
Damages received with incurred interest	$ 3,200	¥ 20,430,203
Arezzo Revenue Agency [Member]
Loss Contingency, Estimate [Abstract]
Estimated liability				$ 12,000
Setec [Member]
Loss Contingency, Estimate [Abstract]
Number of subsidiaries named in the lawsuit \| Subsidiary								3
Setec [Member] \| Dongguan Transpower [Member]
Loss Contingency, Estimate [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]
Loss Contingency, Estimate [Abstract]
Number of defendants \| Defendant				3	3	3
Damages sought				$ 3,200
Damages awarded \| ¥						¥ 20,133,174.10
Jinmei Entities [Member]
Loss Contingency, Estimate [Abstract]
Damages received with incurred interest \| ¥			¥ 20,133,174