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Note 2 - Acquisitions - Proforma Results (Details) - Majority Products Business of CUI Power [Member] - USD ($) | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2020 | Jun. 30, 2020
Revenue | $ 135,847 | $ 270,504
Net earnings | $ 3,383 | $ 5,069
Common Class A [Member] |  |
Earnings per common share - basic and diluted (in dollars per share) | $ 0.26 | $ 0.39
Earnings per common share - basic and diluted (in dollars per share) | (0.26) | (0.39)
Common Class B [Member] |  |
Earnings per common share - basic and diluted (in dollars per share) | (0.28) | (0.42)
Earnings per common share - basic and diluted (in dollars per share) | $ 0.28 | $ 0.42

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