Aggregate notional amount of derivative expressed in nonmonetary units. For example, the number of barrels specified in a fuel oil forward purchase contract.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
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Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
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- Definition

When an investment contract or contracts have a range of settlement dates, the latest settlement date.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
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-Number 210
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When an investment contract or contracts have a range of settlement dates, the earliest settlement date.

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- Definition

Amount of right to receive cash collateral under master netting arrangements that have not been offset against derivative liabilities.

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-Name Accounting Standards Codification
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The estimated value of gains (losses), net anticipated to be transferred in the future from accumulated other comprehensive income into earnings.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Derivative Instruments and Hedging Activities (Details) € in Millions, $ in Millions, $ in Millions	6 Months Ended
	Jun. 30, 2019 USD ($) MMBTU MW t lb	Jun. 30, 2019 CAD ($) MMBTU MW t lb	Jun. 30, 2019 EUR (€) MMBTU MW t lb	Dec. 31, 2018 CAD ($) MMBTU MW t lb	Dec. 31, 2018 EUR (€) MMBTU MW t lb
Derivative [Line Items]
Derivative, Collateral, Right to Reclaim Cash	$ 0.0
Commodity Contract [Member] \| Natural Gas [Member]
Derivative [Line Items]
Nonmonetary Notional Amount of Derivatives \| MMBTU	37,465,000	37,465,000	37,465,000	39,868,000	39,868,000
Beginning Settlement Date	Jul. 01, 2019
Ending Settlement Date	Mar. 31, 2021
Gains (losses) expected to be reclassified into cost of products sold within the next twelve months	$ (9.8)
Commodity Contract [Member] \| Zinc [Member]
Derivative [Line Items]
Nonmonetary Notional Amount of Derivatives \| lb	38,850,000	38,850,000	38,850,000	52,150,000	52,150,000
Beginning Settlement Date	Jul. 01, 2019
Ending Settlement Date	Mar. 31, 2021
Gains (losses) expected to be reclassified into cost of products sold within the next twelve months	$ (2.6)
Commodity Contract [Member] \| Iron Ore [Member]
Derivative [Line Items]
Nonmonetary Notional Amount of Derivatives \| t	2,140,000	2,140,000	2,140,000	2,125,000	2,125,000
Beginning Settlement Date	Jul. 01, 2019
Ending Settlement Date	Jun. 30, 2021
Commodity Contract [Member] \| Electricity [Member]
Derivative [Line Items]
Nonmonetary Notional Amount of Derivatives \| MW	1,240,450	1,240,450	1,240,450	1,461,000	1,461,000
Beginning Settlement Date	Jul. 01, 2019
Ending Settlement Date	Dec. 31, 2020
Gains (losses) expected to be reclassified into cost of products sold within the next twelve months	$ (3.9)
Foreign Exchange Contract [Member] \| Euro Member Countries, Euro
Derivative [Line Items]
Derivative, Notional Amount \| €			€ 4.5		€ 4.0
Beginning Settlement Date	Jul. 01, 2019
Ending Settlement Date	Nov. 30, 2019
Foreign Exchange Contract [Member] \| Canada, Dollars
Derivative [Line Items]
Derivative, Notional Amount		$ 109.6		$ 118.6
Beginning Settlement Date	Jul. 01, 2019
Ending Settlement Date	Dec. 31, 2021
Gains (losses) expected to be reclassified into cost of products sold within the next twelve months	$ (1.3)