CONSOLIDATED STATEMENTS OF INCOME (Unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019
Income Statement [Abstract]
Net sales	$ 585.4	$ 609.9	$ 1,743.8	$ 1,738.8
Cost of sales	475.9	486.7	1,409.0	1,416.9
Gross profit	109.5	123.2	334.8	321.9
Selling, general and administrative expenses	50.8	50.0	159.0	148.3
Restructuring charges	0.0	0.0	2.3	0.0
Operating income	58.7	73.2	173.5	173.6
Interest expense	(4.9)	(7.1)	(15.6)	(20.3)
Other (expense) income, net	(3.9)	1.9	(3.4)	0.1
Income before income taxes	49.9	68.0	154.5	153.4
Income tax expense	10.0	16.9	34.6	35.3
Net income	$ 39.9	$ 51.1	$ 119.9	$ 118.1
EARNINGS PER COMMON SHARE:
Basic (in dollars per share)	$ 0.82	$ 1.06	$ 2.47	$ 2.45
Diluted (in dollars per share)	$ 0.82	$ 1.05	$ 2.46	$ 2.43
WEIGHTED AVERAGE COMMON SHARES OUTSTANDING:
Basic (in shares)	48.1	47.7	48.0	47.7
Diluted (in shares)	48.3	48.1	48.4	48.1