Detail of Certain Balance Sheet Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Detail of Certain Balance Sheet Accounts [Abstract]
Assets, Fair Value Disclosure	$ 763	$ 747
Investments	408	558
Other Assets, Miscellaneous, Noncurrent	3,767	4,760
Other non-current assets	4,938	6,065
Accounts Payable, Trade, Current	85,276	75,293
Accounts Receivable, Allowance for Credit Loss	868	650
Accounts Receivable, Allowance for Credit Loss, Writeoff	552	515
Accounts Receivable, Allowance for Credit Loss	1,184	868
Accrued Salaries	42,828	34,058
Accrued Insurance	6,683	6,202
Other Accrued Liabilities, Current	18,122	15,038
Accounts payable and accrued expenses	152,909	130,591
Accounts Receivable, Allowance for Credit Loss, Writeoff	$ (236)	$ (297)