Inventories (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Segment Reporting Information [Line Items]
Raw Materials And Supplies	$ 277.6	$ 351.6
Work In Process	984.9	1,127.0
Finished Goods	162.1	209.0
Total inventories at current cost	1,424.6	1,687.6
Adjustment from current cost to LIFO cost basis	29.4	(76.9)
Inventory valuation reserves	(84.3)	(63.1)
Progress payments	(47.6)	(11.0)
Total inventories, net	1,322.1	1,536.6
LIFO Inventory Amount	976.1	997.3
LIFO provision (benefit)	(80.9)	(75.6)	(25.9)
Effect of LIFO liquidation on income	(3.8)	(1.5)	0.1
High Performance Metals [Member]
Segment Reporting Information [Line Items]
Inventory valuation reserves	35.0
Flat-Rolled Products [Member]
Segment Reporting Information [Line Items]
Inventory valuation reserves	$ 20.5

Inventory, Valuation Reserve, Period Charge

No definition available.

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- Definition

income statement effect of LIFO provision (benefit)

+ References

No definition available.

+ Details

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- Definition

The effect of liquidating LIFO (last in first out) inventory layers on income.

+ References

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- Definition

Amount before last-in first-out (LIFO) and valuation reserves of merchandise or goods held by the entity that are readily available for sale.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 6

-Subparagraph a

-Article 5

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- Definition

Gross amount, as of the balance sheet date, of merchandise, goods, commodities, or supplies held for future sale or to be used in manufacturing, servicing or production process.

+ References

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- Definition

Reflects the difference between (a) inventory at the lower of LIFO cost or market and (b) inventory at replacement cost or at the lower of some acceptable inventory accounting method (such as FIFO or average cost), or market. If material, reflects an excess of replacement or current cost over stated LIFO value parenthetically on the balance sheet or in a note to the financial statements.

+ References

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- Definition

Carrying amount (lower of cost or market) as of the balance sheet date of inventories less all valuation and other allowances. Excludes noncurrent inventory balances (expected to remain on hand past one year or one operating cycle, if longer).

+ References

+ Details

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- Definition

Gross amount of unprocessed materials to be used in manufacturing or production process and supplies that will be consumed.

+ References

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

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-Name Regulation S-X (SX)

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- Definition

The amount of the valuation account as of the balance sheet date which reduces the carrying amount of inventory to net realizable value; takes into consideration such factors as market value, excessive quantities based on expected sales, technological obsolescence, and shrinkage. May also provide for estimated product returns or price concessions pertaining to product cost.

+ References

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-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 43

-Section A

-Paragraph 9

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Name Regulation S-X (SX)

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- Definition

Gross amount of merchandise or goods which are partially completed, are generally comprised of raw materials, labor and factory overhead costs, and which require further materials, labor and overhead to be converted into finished goods, and which generally require the use of estimates to determine percentage complete and pricing.

+ References

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

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-Name Regulation S-X (SX)

-Number 210

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- Definition

The amount of LIFO (last in first out) inventory present at the reporting date when inventory is also valued using different valuation methods.

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- Definition

Amount of advances received from customers under long-term contracts which have been offset against inventories accounts at the balance sheet date.

+ References

+ Details

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