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ACQUISITIONS AND DISPOSITION (Details) - USD ($) $ / shares in Units, $ in Thousands |  |  |  | 3 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | ---
Jan. 23, 2015 | Jul. 25, 2014 | Jun. 19, 2014 | Sep. 30, 2015 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Payment for acquisitions, net of cash acquired |  |  |  |  | $ 0 | $ 0 |  | $ 208,693 |
Revenues |  |  |  |  | 500,153 | 567,080 | [1] | 487,076 | [1]
Operating income (loss) |  |  |  |  | (76,512) | 28,600 | [1] | 13,472 | [1]
Disposition Sale of NPS [Abstract] |  |  |  |  |  |  |  |  |
Deferred revenue |  |  |  |  | $ 0 | 4,500 |  |  |
Network Power Systems [Member] |  |  |  |  |  |  |  |  |
Disposition Sale of NPS [Abstract] |  |  |  |  |  |  |  |  |
Number of months of manufacturing service agreement |  |  |  |  | 24 months |  |  |  |
Deferred revenue | $ 9,000 |  |  |  |  |  |  |  |
Disposal of assets, net sales |  |  |  |  | $ 4,500 | 4,500 |  |  |
Network Power Systems [Member] | Unipower LLC [Member] |  |  |  |  |  |  |  |  |
Disposition Sale of NPS [Abstract] |  |  |  |  |  |  |  |  |
Proceeds from sale of business | 9,000 |  |  |  |  |  |  |  |
Escrow on sale of business assets | $ 1,000 |  |  |  |  |  |  |  |
Power Solutions [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Payment for acquisitions, net of cash acquired |  |  | $ 109,900 |  |  |  |  |  |
Percentages of owned joint venture investment |  |  | 49.00% |  |  |  |  |  |
Other income |  |  |  | $ 4,200 |  |  |  |  |
Connectivity Solutions [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Payment for acquisitions, net of cash acquired |  | $ 98,800 |  |  |  |  |  |  |
2014 Acquired Companies [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Acquisition-related costs |  |  |  |  |  | 600 |  | 7,300 |
Revenues |  |  |  |  | 195,600 | 230,300 |  | 134,300 |
Operating income (loss) |  |  |  |  | $ 3,800 | $ 10,300 |  | (2,500) |
Acquisition-related costs excluded from pro forma net earnings |  |  |  |  |  |  |  | 14,900 |
Acquisition-related costs incurred but excluded from pro forma earnings during the period after tax |  |  |  |  |  |  |  | 9,800 |
Unaudited Pro forma Consolidated Results of Operations |  |  |  |  |  |  |  |  |
Revenue |  |  |  |  |  |  |  | 629,132 |
Net earnings |  |  |  |  |  |  |  | $ 11,705 |
2014 Acquired Companies [Member] | Class A [Member] |  |  |  |  |  |  |  |  |
Unaudited Pro forma Consolidated Results of Operations |  |  |  |  |  |  |  |  |
Earnings per common share - basic and diluted (in dollars per share) |  |  |  |  |  |  |  | $ 0.94 |
2014 Acquired Companies [Member] | Class B [Member] |  |  |  |  |  |  |  |  |
Unaudited Pro forma Consolidated Results of Operations |  |  |  |  |  |  |  |  |
Earnings per common share - basic and diluted (in dollars per share) |  |  |  |  |  |  |  | $ 1.02 |
[1] | (Revised)

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