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Business Segments (Details2) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Segment Reporting Other Significant Reconciling Item [Line Items] |  |  |
Depreciation and amortization | $ 151.1 | $ 156.4 | $ 160.8
Capital expenditures | 168.2 | 139.2 | 122.7
Operating Segments |  |  |
Segment Reporting Other Significant Reconciling Item [Line Items] |  |  |
Depreciation and amortization | 151.1 | 156.4 | 160.8
Capital expenditures | 168.2 | 139.2 | 122.7
Operating Segments | High Performance Materials & Components |  |  |
Segment Reporting Other Significant Reconciling Item [Line Items] |  |  |
Depreciation and amortization | 84.7 | 90.6 | 91.5
Capital expenditures | 119.9 | 71.7 | 52.7
Operating Segments | Advanced Alloys & Solutions |  |  |
Segment Reporting Other Significant Reconciling Item [Line Items] |  |  |
Depreciation and amortization | 63.5 | 62.9 | 63.4
Capital expenditures | 47.4 | 64.5 | 69.1
Operating Segments | Corporate [Member] |  |  |
Segment Reporting Other Significant Reconciling Item [Line Items] |  |  |
Depreciation and amortization | 2.9 | 2.9 | 5.9
Capital expenditures | $ 0.9 | $ 3.0 | $ 0.9

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