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Stock-Based Compensation - Additional Information (Details) - USD ($)	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Sep. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, granted (in shares)	0
Compensation cost, not yet recognized	$ 2,000
Fair value of shares	1,578,000		$ 1,058,000
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	$ 1,000	$ 13,900
Nonqualified Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, granted (in shares)	0
Expected dividend yield	0.00%
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	$ 300,000	$ 4,000
Compensation cost, not yet recognized	$ 1,000,000.0
Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	306,390
Employees \| Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (Year)	4 years
Expiration period (Year)	10 years
Employees \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of shares	$ 600,000
Employees \| Minimum \| Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (Year)	3 years
Employees \| Minimum \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (Year)	1 year
Employees \| Maximum \| Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (Year)	5 years
Employees \| Maximum \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (Year)	3 years
Board Of Directors \| Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration period (Year)	10 years
The 2015 Incentive Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, capital shares reserved for future issuance (in shares)	2,100,415
Number of shares available for grant (in shares)	483,240