Business Segments (Details 2) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2015	Mar. 31, 2014	Jun. 30, 2014
Segment Data
Net sales	$ 570.6	$ 566.3	$ 1,668.8	$ 1,568.4
Operating income	4.8	49.5	71.9	152.8
Depreciation and Amortization	30.7	27.5	91.2	80.9
Capital Expenditures	24.8	93.6	152.3	298.2
Total Assets	2,967.4		2,967.4		3,057.5
Operating
Segment Data
Pension earnings, interest and deferrals	(2.4)	(6.0)	(7.1)	(15.8)
Corporate
Segment Data
Operating income	(38.6)	(9.5)	(55.9)	(33.7)
Depreciation and Amortization	1.0	1.4	3.3	4.3
Capital Expenditures	1.5	0.3	2.8	3.4
Total Assets	103.7		103.7		144.9
Intersegment
Segment Data
Net sales	(19.6)	(15.8)	(59.3)	(48.4)
Operating income	(0.6)	0.3	(1.9)	(0.7)
Depreciation and Amortization	0.1	(0.1)	(0.5)	(0.5)
Capital Expenditures		(0.3)	(1.0)	(0.7)
Total Assets	(39.6)		(39.6)		(33.9)
Specialty Alloys Operations | Operating
Segment Data
Net sales	469.8	452.0	1,344.0	1,254.5
Operating income	37.9	51.6	106.0	169.7
Depreciation and Amortization	23.9	20.3	70.7	59.4
Capital Expenditures	15.2	89.3	119.5	279.1
Total Assets	2,387.6		2,387.6		2,454.8
Performance Engineered Products | Operating
Segment Data
Net sales	120.4	130.1	384.1	362.3
Operating income	8.5	13.1	30.8	33.3
Depreciation and Amortization	5.7	5.9	17.7	17.7
Capital Expenditures	8.1	4.3	31.0	16.4
Total Assets	$ 515.7		$ 515.7		$ 491.7