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Inventories (Narrative) (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017
Inventories [Line Items] |  |
Inventories stated on the LIFO basis | $ 18.2 | $ 21.9
Inventories stated value below replacement costs | 16.4 | 15.9
PE Films [Member] |  |
Inventories [Line Items] |  |
Cost of goods sold stated at below current replacement costs | $ 0.3 | $ 1.5

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- Definition Inventories [Line Items] + References No definition available. + Details
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- Definition The effect of liquidating LIFO (last in first out) inventory layers on income. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 330 -SubTopic 10 -Section S99 -Paragraph 3 -Subparagraph (SAB Topic 11.F) -URI http://asc.fasb.org/extlink&oid=27011343&loc=d3e100079-122729 + Details
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- Definition The excess of replacement or current cost over the stated LIFO (last in first out) inventory value when the LIFO inventory method is utilized. + 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 210.5-02.6(c)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition The amount of LIFO (last in first out) inventory present at the reporting date when inventory is also valued using different valuation methods. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6361739&loc=d3e7789-107766 + Details
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