Accrued Liabilities (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013
Accrued liabilities
Compensation and benefits	$ 76,169	$ 70,802
Interest payable	40,843	36,311
Deferred revenue	21,506	20,890
Rental obligations	12,289	11,340
Property and other taxes	4,464	4,373
Insurance reserves	9,407	11,109
Operating accruals and other	34,091	29,937
Total accrued liabilities	$ 198,769	$ 184,762