Summary of Significant Accounting Policies (Guarantees) (Details) - USD ($)	12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Guarantees
Balance as of October 1	$ 30,800,000	$ 29,700,000
Balance as of September 30	29,600,000	30,800,000
Standard Product Warranty Accrual, Increase for Warranties Issued	22,500,000	18,300,000
Standard Product Warranty Accrual, Decrease for Payments	$ (23,800,000)	$ (17,500,000)
Warranty term, generally	1 year