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Note 2 - Acquisitions - Proforma Results (Details) - Majority Products Business of CUI Power [Member] - USD ($) | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018
Revenue | $ 522,128 | $ 588,425
Net earnings | $ (7,715) | $ 25,232
Common Class A [Member] |  |
Earnings per common share - basic and diluted (in dollars per share) | $ (0.63) | $ 1.98
Common Class B [Member] |  |
Earnings per common share - basic and diluted (in dollars per share) | $ (0.63) | $ 2.11

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