Leases - Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Cash Flow, Operating Activities, Lessee [Abstract]
Operating cash flows from operating leases	$ 2,532	$ 2,215	$ 7,530	$ 6,089
Operating cash flows from finance leases	8	22	35	77
Financing cash flows from finance leases	$ 269	$ 297	$ 881	$ 880