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Summary of Significant Accounting Policies, Narrative (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2017 | Sep. 30, 2016 | Mar. 31, 2016 | Sep. 30, 2017 | Sep. 30, 2016 | Dec. 31, 2016
Significant accounting policies |  |  |  |  |  |
Inventory Write-down | $ 0.0 | $ 0.0 | $ 4.9 | $ 0.0 | $ 4.9 |
Workers Compensation Liability Undiscounted | 26.6 |  |  | $ 26.6 |  | $ 26.8
Workers' Compensation Discount, Percent |  |  |  | 2.00% |  | 2.00%
Accrued liabilities for employee healthcare benefits | 3.3 |  |  | $ 3.3 |  | $ 3.6
Fabricated Products |  |  |  |  |  |
Significant accounting policies |  |  |  |  |  |
Excess of current cost over the stated LIFO value of inventory | $ (12.5) |  |  | $ (12.5) |  | $ 8.5

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- Definition Carrying value as of the balance sheet date of obligations, excluding pension and other postretirement benefits, incurred through that date and payable for perquisites provided to employees pertaining to services received from them. + 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 210.7-03.15(a)) -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 210.9-03.15(5)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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- Definition Percent discount applied to worker's compensation reserve liability to reduce the reserve to present value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=6482852&loc=d3e14931-158439 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.13(b)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=65670824&loc=d3e14754-158437 + Details
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