Supplemental Financial Information - Long-Lived Assets (Details) - USD ($) $ in Millions	Sep. 30, 2025	Sep. 30, 2024
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	$ 279.6	$ 314.1
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	85.0	105.0
Europe, Middle East, and Africa
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	159.7	170.8
Asia
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	33.3	37.2
Other
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	$ 1.6	$ 1.1