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Employee Benefits, Net Periodic Benefit Costs and Charges Relating To All Other Employee Benefit Plans(Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Gain on removal of Union VEBA net assets | $ 0.0 | $ 0.0 | $ 0.0 | $ (1.3)
Total net periodic postretirement benefit cost relating to Salaried VEBA |  |  | 3.0 | 2.2
Total other employee benefit plans | 4.9 | 4.2 | 12.0 | 10.2
Fabricated Products |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Deferred compensation plan | 0.4 | 0.1 | 0.4 | 0.2
Defined contribution plans | 1.3 | 1.4 | 5.1 | 5.5
Multiemployer pension plans | 1.1 | 1.2 | 2.3 | 2.3
Total other employee benefit plans | 2.8 | 2.7 | 7.8 | 8.0
All Other |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Deferred compensation plan | 0.5 | 0.3 | 0.6 | 0.7
Defined contribution plans | 0.0 | 0.1 | 0.5 | 0.6
Total other employee benefit plans | 2.1 | 1.5 | 4.2 | 2.2
VEBAs | All Other |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Gain on removal of Union VEBA net assets | 0.0 | 0.0 | 0.0 | (1.3)
Total net periodic postretirement benefit cost relating to Salaried VEBA | 1.6 | 1.1 | 3.1 | 2.2
Salaried VEBA: |  |  |  |
Interest cost | 0.7 | 0.8 | 1.4 | 1.5
Expected return on plan assets | (0.7) | (1.1) | (1.4) | (2.1)
Amortization of prior service cost | 1.4 | 1.2 | 2.7 | 2.4
Amortization of net actuarial loss | $ 0.2 | $ 0.2 | $ 0.4 | $ 0.4

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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=96867065&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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