Trade Accounts Receivable (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Sep. 30, 2018
Current trade accounts receivable
Trade accounts receivable	$ 25,144	$ 15,776
Allowance for doubtful accounts	(951)	(1,453)
Total current trade accounts receivable	$ 24,193	$ 14,323

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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