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Note 7 - Income Taxes (Details Textual) - State and Local Jurisdiction [Member] - USD ($) $ in Millions | 3 Months Ended
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Sep. 30, 2022 | Jun. 30, 2022 | Jun. 30, 2021
Iowa, Arkansas, and Idaho Department of Revenue [Member] |  |  |
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability | $ (40) |  |
Nebraska Department of Revenue [Member] |  |  |
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability |  | $ (55) |
Nebraska, Oklahoma, and Idaho Department of Revenue [Member] |  |  |
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability |  |  | $ (43)

X
- Definition Amount of income tax expense (benefit) from continuing operations attributable to an adjustment of a deferred tax liability or asset for enacted changes in tax laws or rates or a change in the tax status of the entity. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (g) -URI https://asc.fasb.org/extlink&oid=121826272&loc=d3e32639-109319 + Details
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- Details
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