CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2023
Income Statement [Abstract]
Net sales	$ 2,877.1	$ 2,759.7	$ 2,550.3
Cost of sales	2,108.5	2,175.4	2,213.0
Gross profit	768.6	584.3	337.3
Selling, general and administrative expenses	243.2	230.2	204.2
Goodwill impairment charge	0.0	14.1	0.0
Restructuring and asset impairment charges	3.6	16.9	0.0
Operating income	521.8	323.1	133.1
Interest expense, net	48.4	51.0	54.1
Other expense, net	6.1	60.5	6.5
Income before income taxes	467.3	211.6	72.5
Income tax expense	91.3	25.1	16.1
Net income	$ 376.0	$ 186.5	$ 56.4
EARNINGS PER COMMON SHARE:
Basic (in dollars per share)	$ 7.50	$ 3.75	$ 1.15
Diluted (in dollars per share)	$ 7.42	$ 3.70	$ 1.14
WEIGHTED AVERAGE COMMON SHARES OUTSTANDING:
Basic (in shares)	50.2	49.7	48.8
Diluted (in shares)	50.7	50.3	49.2