Equity-Based Compensation - Fair Value of Underlying Common Stock and Exercise Price of Stock Options (Details) - $ / shares	Sep. 30, 2020	Sep. 30, 2019
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of underlying common stock (dollars per share)	$ 1.19	$ 2.32
Exercise price of common stock option (dollars per share)	1.19	2.32
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of underlying common stock (dollars per share)	2.80	2.95
Exercise price of common stock option (dollars per share)	2.80	2.95
Weighted Average
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of underlying common stock (dollars per share)	1.91	2.75
Exercise price of common stock option (dollars per share)	$ 1.94	$ 2.75