Leases - Narrative (Details)	12 Months Ended
	Sep. 30, 2021 sublease_option sublease
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Number of subleased facilities | sublease	1
Sublease term	5 years
Number of sublease extension options | sublease_option	2
Sublease option extension period	1 year
Weighted-average remaining lease term	8 years 3 months 18 days
Weighted-average discount rate	6.00%
Facilities and Equipment | Minimum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Remaining lease term	1 year 2 months 12 days
Facilities and Equipment | Maximum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Remaining lease term	9 years 6 months