Employee Incentive Plans, Short Term Incentive Plans (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
EVA measurement period			1 year
Compensation charges associated with STI Plans
Total costs recorded in connection with STI plans	$ 3.9	$ 1.9	$ 11.0	$ 6.4
Fabricated Products
Compensation charges associated with STI Plans
Total costs recorded in connection with STI plans	2.6	1.3	7.6	4.7
All Other
Compensation charges associated with STI Plans
Total costs recorded in connection with STI plans	1.3	0.6	3.4	1.7
Cost of products sold
Compensation charges associated with STI Plans
Total costs recorded in connection with STI plans	1.1	0.6	3.4	2.5
Selling, administrative, research and development, and general
Compensation charges associated with STI Plans
Total costs recorded in connection with STI plans	$ 2.8	$ 1.3	$ 7.6	$ 3.9