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DISPOSITION - SALE OF NPS (Details) - Network Power Systems [Member] - USD ($) $ in Millions |  | 12 Months Ended
--- | --- | ---
Jan. 23, 2015 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Disposition Sale of NPS [Abstract] |  |  |  |
Number of months of manufacturing service agreement |  | 24 months |  |
Deferred revenue | $ 9.0 |  |  |
Disposal of assets, net sales |  |  | $ 4.5 | $ 4.5
Unipower LLC [Member] |  |  |  |
Disposition Sale of NPS [Abstract] |  |  |  |
Proceeds from sale of business | 9.0 |  |  |
Escrow on sale of business assets | $ 1.0 |  |  |

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