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Pre-tax loss on settlement of Union VEBA

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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-Section 50

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The total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of derivative instruments, including options, swaps, futures, and forward contracts, held at each balance sheet date, that was included in earnings for the period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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Segment Information, Textuals (Details) $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
Segment Information, Textuals (Details) $ in Millions	Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)	Jun. 30, 2015 USD ($) productionfacilities	Jun. 30, 2014 USD ($)	Dec. 31, 2014
Segment Reporting Information
Unrealized gains (losses) on derivatives			$ (6.0)	$ 4.9
Net periodic postretirement benefit cost relating to Salaried VEBA	$ 0.6	$ (6.1)	1.2	(11.7)
Pre-tax loss on settlement of Union VEBA		0.0
Fabricated Products
Segment Reporting Information
Unrealized gains (losses) on derivatives	$ (1.5)	$ 1.5	$ (6.0)	$ 3.5
United States
Segment Reporting Information
Number of production facilities \| productionfacilities			11
Canada
Segment Reporting Information
Number of production facilities \| productionfacilities			1
Customer Concentration Risk \| Largest Customer \| Sales Revenue, Net \| Fabricated Products
Segment Reporting Information
Concentration Risk, Percentage	25.00%	27.00%	26.00%	27.00%
Customer Concentration Risk \| Largest Customer \| Accounts Receivable
Segment Reporting Information
Concentration Risk, Percentage			20.00%		10.00%
Customer Concentration Risk \| Second Largest Customer \| Sales Revenue, Net \| Fabricated Products
Segment Reporting Information
Concentration Risk, Percentage	10.00%		10.00%
Customer Concentration Risk \| Second Largest Customer \| Accounts Receivable
Segment Reporting Information
Concentration Risk, Percentage					12.00%
VEBAs
Segment Reporting Information
Net periodic postretirement benefit cost relating to Salaried VEBA	$ 0.6	$ (6.1)	$ 1.2	$ (11.7)
Pre-tax loss on settlement of Union VEBA	$ 1.6	$ 0.0	$ 493.8	$ 0.0