Condensed Consolidated Statements of Operations - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Income Statement [Abstract]
Net Sales	$ 342.6	$ 204.2	$ 907.1	$ 705.7
Cost of goods sold	231.3	135.5	616.9	457.5
Gross Profit	111.3	68.7	290.2	248.2
Selling, general and administrative expenses	42.6	32.6	129.1	116.6
Amortization of intangible assets	17.2	5.5	46.3	16.6
Other operating income, net	0.0	0.0	(0.1)	0.0
Operating Profit	51.5	30.6	114.9	115.0
Interest expense, net	9.5	15.3	33.6	41.2
Loss on refinancing of debt	0.1	0.0	1.6	0.0
Earnings before Income Taxes	41.9	15.3	79.7	73.8
Income tax expense	3.4	1.1	5.8	9.2
Net Earnings Including Redeemable Noncontrolling Interest	38.5	14.2	73.9	64.6
Less: Net earnings attributable to redeemable noncontrolling interest	29.0	10.9	56.0	51.1
Net Earnings Available to Class A Common Stockholders	$ 9.5	$ 3.3	$ 17.9	$ 13.5
Earnings per Class A common share, basic (in usd per share)	$ 0.24	$ 0.08	$ 0.45	$ 0.34
Earnings per Class A common share, diluted (in usd per share)	$ 0.24	$ 0.08	$ 0.45	$ 0.34
Weighted Average Class A common shares outstanding, basic (in shares)	39.5	39.4	39.5	39.4
Weighted-Average Class A common shares outstanding, diluted (in shares)	39.7	39.5	39.7	39.5