Revenue Recognition - Additional Information (Details) - USD ($)	12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Disaggregation Of Revenue [Line Items]
Revenue	$ 45,847,000	$ 53,306,000
Cost of revenue recognized from deferred contract cost	27,000
Deferred Revenue
Disaggregation Of Revenue [Line Items]
Deferred contract liabilities	0	200,000
Prepaid Expenses and Other Current Assets
Disaggregation Of Revenue [Line Items]
Deferred contract costs	0	$ 27,000
Deferred Contract Liability
Disaggregation Of Revenue [Line Items]
Revenue	$ 200,000