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Note 2 - Acquisitions (Details Textual) - USD ($) $ in Thousands |  | 3 Months Ended | 12 Months Ended | 13 Months Ended
--- | --- | --- | --- | ---
Dec. 03, 2019 | Mar. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2020
EOS Power Panama Inc. [Member] | Forecast [Member] |  |  |  |  |
Business Combination, Consideration Transferred, Total |  | $ 7,000 |  |  |
Majority Products Business of CUI Power [Member] |  |  |  |  |
Business Combination, Consideration Transferred, Total | $ 32,000 |  |  |  | $ 29,196
Payments to Acquire Businesses, Gross | 32,000 |  |  |  | $ 29,196
Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual |  |  | $ 43,100 | $ 2,200 |
Business Combination, Pro Forma Information, Earnings or Loss of Acquiree since Acquisition Date, Actual |  |  | 6,800 | 400 |
Business Combination, Acquisition Related Costs |  |  | 200 | $ 200 |
Majority Products Business of CUI Power [Member] | Trade Names [Member] |  |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Indefinite-Lived Intangible Assets | 5,000 |  |  |  |
Majority Products Business of CUI Power [Member] | Customer Relationships [Member] |  |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles | $ 11,000 |  |  |  |
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life (Year) | 13 years |  |  |  |
EOS Power Panama Inc. [Member] |  |  |  |  |
Revenues, Total |  |  | $ 12,000 |  |

X
- Definition Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275 + Details
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- Definition This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 25 -Paragraph 23 -URI http://asc.fasb.org/extlink&oid=116868678&loc=d3e1043-128460 + Details
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- Definition Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=116859721&loc=d3e6613-128477 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=120321790&loc=d3e6927-128479 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=116859721&loc=d3e6578-128477 + Details
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- Definition Amount of assets, excluding financial assets and goodwill, that lack physical substance, having a projected indefinite period of benefit, acquired at the acquisition date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=121647850&loc=d3e4845-128472 + Details
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- Definition The amount of identifiable intangible assets recognized as of the acquisition date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 55 -Paragraph 37 -URI http://asc.fasb.org/extlink&oid=121600890&loc=d3e2207-128464 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=121647850&loc=d3e4845-128472 + Details
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- Definition The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=120321790&loc=d3e6927-128479 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3213-108585 + Details
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