Revenue Recognition - Summary of Opening and Closing Balances of Contract Assets and Contract Liabilities (Details) $ in Millions	6 Months Ended
	Mar. 31, 2024 USD ($)
Disaggregation of Revenue [Abstract]
Short-Term Contract Assets, Beginning balance	$ 241.7
Decrease in Short-Term Contract Assets	(5.4)
Short-Term Contract Assets, Ending balance	236.3
Short-Term Contract Liabilities, Beginning balance	13.5
Decrease in Short-Term Contract Liabilities	(8.3)
Short-Term Contract Liabilities, Ending balance	$ 5.2