Condensed Consolidated Balance Sheets (Current Period Unaudited)-parentheticals (Parentheticals) - USD ($) shares in Thousands, $ in Thousands	Dec. 31, 2021	Mar. 31, 2021
Accounts Receivable, Allowance for Credit Loss, Current	$ 19	$ 39
Preferred Stock, Par or Stated Value Per Share (in USD per Share)	$ 0.001	$ 0.001
Preferred Stock, Shares Authorized (in shares)	5,000	5,000
Preferred stock, shares issued (in shares)	3	3
Preferred Stock, Shares Outstanding, Ending Balance (in shares)	3	3
Preferred Stock, Liquidation Preference Per Share (in USD per Share)	$ 4	$ 4
Common Stock, Par or Stated Value Per Share (in USD per Share)	$ 0.001	$ 0.001
Common Stock, Shares Authorized (in shares)	40,000	40,000
Common Stock, Shares, Issued, Total (in shares)	20,957	20,269
Common Stock, Shares, Outstanding, Ending Balance (in shares)	20,957	20,269

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

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