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Business Segments (Details3) - USD ($) $ in Millions | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
--- | --- | --- | ---
Segment Reporting Asset Reconciling Item [Line Items] |  |  |
Identifiable Assets | $ 5,185.4 | $ 5,170.0 | $ 5,751.7
Deferred taxes | 468.9 | 730.6 |
High Performance Materials & Components [Member] |  |  |
Segment Reporting Asset Reconciling Item [Line Items] |  |  |
Identifiable Assets | 2,662.3 | 2,744.3 | 3,355.5
Flat Rolled Products [Member] |  |  |
Segment Reporting Asset Reconciling Item [Line Items] |  |  |
Identifiable Assets | 2,218.4 | 2,056.4 | 2,189.5
Discontinued Operations [Member] |  |  |
Segment Reporting Asset Reconciling Item [Line Items] |  |  |
Identifiable Assets | 0.2 | 0.4 | 0.9
Corporate, Non-Segment [Member] |  |  |
Segment Reporting Asset Reconciling Item [Line Items] |  |  |
Deferred taxes | 7.6 | 12.1 | 0.0
Corporate: Cash and cash equivalents and other [Member] |  |  |
Segment Reporting Asset Reconciling Item [Line Items] |  |  |
Identifiable Assets | $ 296.9 | $ 356.8 | $ 205.8

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- Definition Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(12)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(11)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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- Definition Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b),(c) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319 + Details
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