Trade Accounts and Financing Receivables - Trade Accounts Receivable, Net (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Sep. 30, 2021
Current trade accounts receivable
Trade accounts receivable	$ 11,151	$ 12,635
Allowance for doubtful accounts	(419)	(428)
Total	$ 10,732	$ 12,207

Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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