Operating Leases - Lease Expense and Cash Payments & Weighted-Average Remaining Lease Term and Discount Rate (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Leases [Abstract]
Operating lease expense	$ 963	$ 986	$ 2,920	$ 2,964
Cash payments on lease liabilities	$ 1,027	$ 1,083	$ 3,271	$ 3,259
Weighted-average remaining lease term	7 years 2 months 12 days	4 years 4 months 24 days	7 years 2 months 12 days	4 years 4 months 24 days
Weighted-average discount rate	5.95%	4.45%	5.95%	4.45%