Note 8 - Basic and Diluted Net Loss Per Share - Net Income (Loss) Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Net loss attributable to Avalon Holdings Corporation common shareholders	$ (455)	$ (1,144)
Weighted Average Number of Shares Outstanding, Basic, Total	3,875,431	3,813,796
Potentially dilutive shares from stock options (in shares)
Shares used in computing diluted loss per share (in shares)	3,875,000	3,814,000
Basic and diluted net loss per share (in dollars per share)	$ (0.12)	$ (0.30)

The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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