Trade Accounts and Notes Receivable - Trade Accounts Receivable, Net (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Sep. 30, 2020
Current trade accounts receivable
Trade accounts receivable	$ 5,695	$ 14,090
Allowance for doubtful accounts	(558)	(496)
Total	$ 5,137	$ 13,594

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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