Segment and Geographic Information - Revenue By Geographic Segment (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Segment Reporting Revenue Reconciling Item [Line Items]
Total revenue	$ 457,721	$ 429,050
Operating Segments
Segment Reporting Revenue Reconciling Item [Line Items]
Total revenue	457,721	429,050
Americas | Operating Segments
Segment Reporting Revenue Reconciling Item [Line Items]
Total revenue	212,881	202,279
Europe | Operating Segments
Segment Reporting Revenue Reconciling Item [Line Items]
Total revenue	162,308	162,319
Asia-Pacific | Operating Segments
Segment Reporting Revenue Reconciling Item [Line Items]
Total revenue	$ 82,532	$ 64,452