Note 2 - Acquisitions - Proforma Results (Details) - Majority Products Business of CUI Power [Member] - USD ($)	12 Months Ended
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

The pro forma basic and diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(3)
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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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