Acquisition (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	1 Months Ended	3 Months Ended		12 Months Ended
	Feb. 29, 2012	Sep. 30, 2012	Sep. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Additional disclosure
Acquisition-related costs			$ 1.4
Latrobe Acquisition
Acquisition and strategic partnership disclosures
Shares issued through business acquisition	8.1
Cash paid, net of cash acquired	11.5
Cash acquired	2.5
Increased amounts allocated to accounts payable and accrued liabilities		0.9
Decreased amounts allocated to deferred income taxes		0.3
Increased amounts allocated to goodwill		0.6
Summary of preliminary purchase price allocation
Accounts receivable	67.3
Inventory	241.2
Property, plant and equipment	172.4
Intangible assets	87.1
Other	10.6
Accounts Payable and accrued liabilities	(64.8)
Long-term debt	(153.7)
Pension and other postretirement liabilities	(100.8)
Deferred income taxes	(47.4)
Total identifiable net assets	211.9
Goodwill	215.1
Total purchase price	427.0
Additional disclosure
Acquisition-related costs				11.7	2.4
Transaction costs		5.2
Net sales		127.7
Operating income since acquisition		16.3
Proforma results
Revenue		544.9	542.3
Earnings		$ 39.2	$ 23.5
Earnings per Common Share, Basic (in dollars per share)		$ 0.74	$ 0.45
Earnings per Common Share, Diluted (in dollars per share)		$ 0.74	$ 0.44