Detail of Certain Balance Sheet Accounts (Tables)

12 Months Ended

Sep. 30, 2020

Detail of Certain Balance Sheet Accounts [Abstract]

Accounts Receivable, Allowance for Credit Loss [Table Text Block]

	Year Ended September 30,
	2020		2019
Balance at beginning of period	$	1,184	$	868
Additions to costs and expenses	1,864		552
Deductions for uncollectible receivables written off, net of recoveries	(435)		(236)
Balance at end of period	$	2,613	$	1,184

Schedule of Accounts Payable and Accrued Liabilities [Table Text Block]

	Year Ended September 30,
	2020		2019
Accounts payable, trade	$	93,315	$	85,276
Accrued compensation and benefits	53,933		42,828
Accrued insurance liabilities	6,254		6,683
Current operating lease liabilities	11,056		—
Other accrued expenses	22,152		18,122
	$	186,710	$	152,909

Schedule of Other Assets [Table Text Block]

	Year Ended September 30,
	2020		2019
Executive Savings Plan assets	$	766	$	763
Securities and equity investments	—		408
Other	5,014		3,767
Total	$	5,780	$	4,938