Revenue from Contracts with Customers - Revenue By Geographic Segment (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Mar. 31, 2024	Mar. 31, 2023
Segment Reporting Revenue Reconciling Item [Line Items]
Total revenue	$ 603,072	$ 542,181	$ 1,153,286	$ 1,008,091
Operating Segments
Segment Reporting Revenue Reconciling Item [Line Items]
Total revenue	603,072	542,181	1,153,286	1,008,091
Americas | Operating Segments
Segment Reporting Revenue Reconciling Item [Line Items]
Total revenue	260,622	256,376	527,889	483,288
Europe | Operating Segments
Segment Reporting Revenue Reconciling Item [Line Items]
Total revenue	257,309	209,066	454,262	376,276
Asia-Pacific | Operating Segments
Segment Reporting Revenue Reconciling Item [Line Items]
Total revenue	$ 85,141	$ 76,739	$ 171,135	$ 148,527