Accrued Expenses and Other Current Liabilities - Schedule of Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Sep. 30, 2017
Payables And Accruals [Abstract]
Payroll related accruals	$ 47,442	$ 49,573
Accrued operating expenses	46,521	63,590
Other accruals	23,928	23,953
Accrued expenses and other current liabilities	$ 117,891	$ 137,116

Amount of expenses incurred but not yet paid classified as other, due within one year or the normal operating cycle, if longer.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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