Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019
Earnings Per Share [Abstract]
Net earnings/(loss)	$ 20.9	$ 31.7	$ 66.5	$ 66.3
Participating Securities, Distributed and Undistributed Earnings (Loss), Basic	(9.1)	0.0	(27.8)	0.0
Net Income (Loss) Available to Common Stockholders, Basic	$ 11.8	$ 31.7	$ 38.7	$ 66.3
Weighted average shares outstanding	151,267,795	145,145,310	147,647,548	143,896,635
Dilutive securities issuable-stock plans	1,787,847	1,612,961	1,843,559	1,696,575
Total weighted average diluted shares outstanding	153,055,642	146,758,271	149,491,107	145,593,210
Earnings Per Share, Basic	$ 0.08	$ 0.22	$ 0.26	$ 0.46
Earnings Per Share, Diluted	$ 0.08	$ 0.22	$ 0.26	$ 0.46