Other Balance Sheet Information - Capitalized Direct Costs (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Jun. 30, 2022	Jun. 30, 2022	Sep. 30, 2021
Property, Plant and Equipment, Gross [Abstract]
Capitalized computer software, gross	$ 25.5	$ 25.5	$ 22.7
Capitalized computer software costs	1.2	2.8
Software Development
Property, Plant and Equipment, Gross [Abstract]
Capitalized computer software, gross	$ 7.5	$ 7.5