Revenue Recognition - Additional Information (Details) - USD ($)	3 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Sep. 30, 2019
Disaggregation Of Revenue [Line Items]
Deferred contract liabilities	$ 0		$ 0
Deferred contract costs	0		$ 0
Revenue	9,083,000	$ 10,459,000
Cost of revenue recognized from deferred contract cost	0	8,000
Deferred Contract Liability
Disaggregation Of Revenue [Line Items]
Revenue	$ 0	$ 100,000