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Note 9 - Fair Value (Details Textual) - USD ($) | 3 Months Ended | 15 Months Ended
--- | --- | ---
Mar. 31, 2022 | Mar. 31, 2021 | Mar. 31, 2022
Fair Value Adjustment of Warrants | $ (1,837,211) | $ (2,175,824) |
Boston Omaha [Member] |  |  |
Equity Securities, FV-NI, Realized Gain (Loss), Total | $ 15,000,000 | $ 3,000,000 | $ 61,000,000

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- Definition Amount of expense (income) related to adjustment to fair value of warrant liability. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3602-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 480 -SubTopic 10 -Section 25 -Paragraph 13 -URI https://asc.fasb.org/extlink&oid=109262497&loc=d3e20148-110875 + Details
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