Revenue Recognition - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Sep. 30, 2020
Disaggregation of Revenue [Line Items]
Sales	$ 12,749	$ 13,962
Contract assets	1,200		$ 600
Contract liabilties	100		$ 100
Contract liabilities, revenue recognized	$ 100
Customer Concentration Risk \| Revenue Benchmark \| Largest Customer
Disaggregation of Revenue [Line Items]
Consolidate revenues, percentage of sales	15.00%	11.00%
Central and South America
Disaggregation of Revenue [Line Items]
Sales	$ 300	$ 400

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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