Summary of Significant Accounting Policies Revenue Recognition - Impact on Income Statement (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Net revenue	$ 607.5	$ 446.6	$ 1,823.3	$ 1,321.5
Cost of goods sold	400.2	298.2	1,250.5	865.2
Gross profit	207.3	148.4	572.8	456.3
Operating expenses	118.5	90.8	411.9	275.2
Income before income taxes	53.3	43.3	(30.3)	140.1
Income tax expense	28.3	11.6	17.7	39.9
Consolidated net income (loss)	$ 25.0	$ 31.7	$ (48.0)	$ 100.2