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Note 3 - Sale of Equity Interests in Rio Bravo (Details Textual) - Rio Bravo [Member] - USD ($) $ in Millions | Mar. 02, 2020 | Feb. 13, 2020 | Jun. 30, 2022
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Equity Method Investment, Ownership Percentage |  | 100.00% |
Disposal Group, Including Discontinued Operation, Consideration | $ 19.4 |  |
Proceeds from Divestiture of Businesses | $ 15.0 |  |
Equity Method Investments, Rights to The Natural Gas Firm Transportation Capacity Term (Year) |  | 20 years |
Sale of Business, Failure to Issue Notice, Maximum Right Price to Sell Back Equity Interests |  |  | $ 23.0

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- Definition Represents term of rights to the natural gas firm transportation capacity. + References No definition available. + Details
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- Definition The maximum right price to sell back equity interests after the failure to issue a notice in the sale of a business. + References No definition available. + Details
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- Definition The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3179-108585 + Details
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