Income Taxes - Reconciliation of the Reserve For Uncertain Tax Positions (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Jun. 30, 2022	Sep. 30, 2021
Reconciliation of the reserve for uncertain tax positions
Beginning balance	$ 8,032	$ 11,410
Gross (decreases) increases - tax positions in prior period	396	542
Additions for prior year tax positions	1,761	2,060
Reductions for prior year tax positions	(2,250)	(3,746)
Unrecognized Tax Benefits, Decrease Resulting from Settlements with Taxing Authorities	0	(976)
Reductions for expirations of statute of limitations	(1,223)	(1,258)
Uncertain tax positions, end of year	$ 6,716	$ 8,032