Other Long-Term Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Sep. 30, 2021
Other long-term assets [Abstract]
Interest rate swap	$ 36,902	$ 12,335
Right of use assets	25,738	29,302
Prepaid unamortized debt issuance cost - revolver	2,151	2,201
SERP investments	1,541	1,439
Vendor contract assets	732	1,329
Other long-term assets	4,786	5,378
Total	$ 71,850	$ 51,984