Retirement Plan - Additional Information (Detail) - 401(k) plan [Member] - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Defined Contribution Plan Disclosure [Line Items]
Defined contribution plan employer discretionary contribution	$ 190	$ 190
Defined contribution plan description	Employees are eligible to participate if they are over 21 years of age and have completed a minimum of one month of service with 80 hours worked in that month.
Defined contribution plan employee eligibility age	21 years
Defined contribution plan minimum eligible service months	1 month
Defined contribution plan minimum eligible service hours	80 hours
Defined contribution plan name	401(k) retirement plan
Discretionary Contributions [Member]
Defined Contribution Plan Disclosure [Line Items]
Defined contribution plan description	To be eligible for the discretionary profit-sharing contribution, an employee must have completed a minimum of six consecutive months of service with 80 hours of service in each month.
Defined contribution plan employee eligibility age	21 years
Defined contribution plan minimum eligible service months	6 months
Defined contribution plan minimum eligible service hours in each month	80 hours