Leases - Lease Cost (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Leases [Abstract]
Operating lease expense	$ 15,699	$ 15,624	$ 47,237	$ 47,603
Variable lease expense	3,601	3,025	9,768	8,925
Other	(845)	0	(2,570)	0
Total lease expense	$ 18,455	$ 18,649	$ 54,435	$ 56,528