Goodwill and Other Intangible Assets, Net (Details) (USD $) In Millions, unless otherwise specified	0 Months Ended	12 Months Ended
	Feb. 28, 2014	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2012
Goodwill disclosures
Impairment of goodwill	$ 0	$ 0
Changes in the carrying amount of goodwill by reportable segment
Goodwill		292.4	292.4	295.2
Accumulated impairment losses		(34.7)	(34.7)	(34.7)
Total goodwill		257.7	257.7	260.5
Other			(2.8)
Specialty Alloys Operations
Changes in the carrying amount of goodwill by reportable segment
Total goodwill		195.5	195.5	202.9
Other			(7.4)
Carpenter Powder Products
Changes in the carrying amount of goodwill by reportable segment
Total goodwill			3.4
Performance Engineered Products
Changes in the carrying amount of goodwill by reportable segment
Total goodwill		62.2	62.2	57.6
Other			$ 4.6