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Inventories Schedule of Inventory Valuation Impact on Income (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Inventory Disclosure [Abstract] |  |  |
LIFO benefit (charge) | $ (28.6) | $ (54.2) | $ (39.1)
NRV benefit (charge) | 27.9 | 54.0 | 39.9
Net cost of sales impact | $ (0.7) | $ (0.2) | $ 0.8

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- Definition Inventory, Net Realizable Value Reserve, Period Charge + References No definition available. + Details
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- Definition Lifo Provision Benefit and Change in Debit LIFO NRV reserve, net + References No definition available. + Details
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- References No definition available. + Details
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- Definition The change in the inventory reserve representing the cumulative difference in cost between the first in, first out and the last in, first out inventory valuation methods, which change has been reflected in the statement of income during the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.6b) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.6c) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.6a) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 330 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 5.L) -URI http://asc.fasb.org/extlink&oid=27011343&loc=d3e99989-122729 + Details
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