Accounts Receivable (Details) - USD ($) $ in Thousands	6 Months Ended
	Mar. 31, 2022	Sep. 30, 2021
Receivables [Abstract]
Accounts receivable	$ 289,462	$ 282,819
Allowance for credit losses	(6,370)	(4,824)
Accounts receivable, net	283,092	$ 277,995
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at September 30, 2020	(4,824)
Charged to costs and expenses	(1,134)
Write-offs	146
Foreign currency and other	(558)
Balance at December 31, 2020	$ (6,370)