Leases - Additional information related to leases (Details) $ in Thousands	12 Months Ended
	Sep. 30, 2020 USD ($)
Cash paid for amounts included in the measurement of lease liabilities
Operating cash flows from operating leases	$ 5,223
Operating cash flows from finance leases	971
Financing cash flows from finance leases	1,547
Right-of-use assets obtained in exchange for lease liabilities
Right-of-use assets obtained in exchange for operating lease liabilities	$ 26,244
Weighted-average remaining lease term
Operating leases	6 years
Finance leases	12 years 6 months 10 days
Weighted-average discount rate
Operating leases	3.09%
Finance leases	4.30%