Note 2 - Reportable Segments - Assets by Operating Segment (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Assets	$ 127,547	$ 110,787
Water and Land Resources [Member]
Assets	124,050	107,439
Water Treatment [Member]
Assets	$ 3,497	$ 3,348

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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+ Details