Consolidated Balance Sheets (Parentheticals) - USD ($) shares in Thousands, $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Provision for doubtful accounts	$ 69	$ 210
Common stock, par value (in dollars per share)	$ 1.00	$ 1.00
Common stock, authorized (in shares)	20,000	20,000
Common stock, issued (in shares)	9,179	8,951
Common stock, outstanding (in shares)	9,179	8,951

Amount of allowance for credit loss on accounts receivable, classified as current.

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Face amount or stated value per share of common stock.

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