Trade Accounts Receivable and Financing Receivables - Trade Accounts Receivable, Net (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Sep. 30, 2019
Current trade accounts receivable
Trade accounts receivable	$ 33,641	$ 25,144
Allowance for doubtful accounts	(960)	(951)
Total	$ 32,681	$ 24,193

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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