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Employee Benefits, Total charges (income) related to all benefit plans (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
(Gain) loss on removal of Union VEBA net assets – Note 6 |  | $ (0.1) | $ 493.4 | $ 0.0
Components of Net Periodic Benefit Cost (Income) |  |  |  |
Net periodic benefit cost (income) | [1] | 3.7 | 2.8 | (23.5)
Contributions of the Company |  | 4.7 | 4.4 | 4.0
Defined Benefit Plan Net Periodic Benefit Cost And Charges Relating To Other Benefit Plans |  | 18.1 | 509.6 | (10.4)
Fabricated Products |  |  |  |
Components of Net Periodic Benefit Cost (Income) |  |  |  |
Deferred Compensation Arrangement with Individual, Compensation Expense |  | 0.2 | 0.1 | 0.2
Defined Contribution Plan, Cost Recognized |  | 8.1 | 7.8 | 7.3
Defined Benefit Plan Net Periodic Benefit Cost And Charges Relating To Other Benefit Plans |  | 13.3 | 12.7 | 11.8
Fabricated Products | Canadian pension plan |  |  |  |
Components of Net Periodic Benefit Cost (Income) |  |  |  |
Net periodic benefit cost (income) |  | 0.3 | 0.4 | 0.3
All Other |  |  |  |
Components of Net Periodic Benefit Cost (Income) |  |  |  |
Deferred Compensation Arrangement with Individual, Compensation Expense |  | 0.7 | 0.3 | 0.7
Defined Contribution Plan, Cost Recognized |  | 0.8 | 0.8 | 0.8
Defined Benefit Plan Net Periodic Benefit Cost And Charges Relating To Other Benefit Plans |  | 4.8 | 496.9 | (22.2)
All Other | VEBAs |  |  |  |
Components of Net Periodic Benefit Cost (Income) |  |  |  |
Net periodic benefit cost (income) |  | $ 3.4 | $ 2.4 | $ (23.7)
[1] | See Note 6 for the impact of removing the Union VEBA (defined in Note 6) net assets.

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- Definition The compensation expense recognized during the period pertaining to the deferred compensation arrangement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 710 -SubTopic 10 -Section 30 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6409875&loc=d3e20015-108363 + Details
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- Definition The amount of decrease that is related to an event that significantly reduces the expected years of future service of present employees or eliminates for a significant number of employees the accrual of defined benefits for some or all of their future services. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(10) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Plan Curtailment -URI http://asc.fasb.org/extlink&oid=6520938 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 30 -Section 15 -Paragraph 6 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=7577095&loc=d3e8001-114927 + Details
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