Revenue Recognition- Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Disaggregation of Revenue [Line Items]
Sales	$ 50,182	$ 55,118
Unbilled revenue	590	2,691
Deferred revenue	$ 113	97
Revenue Benchmark \| Customer Concentration Risk \| Largest Customer
Disaggregation of Revenue [Line Items]
Concentration risk, percentage	14.00%
International Regions Excluding Central America and South America
Disaggregation of Revenue [Line Items]
Sales	$ 1,900	2,400
Contract with customer, asset, after allowance for credit loss		2,700
Contract with customer, liability		$ 100

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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