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

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

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.

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=112277219&loc=d3e80845-113994

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- Definition

Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 4CC
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- Definition

Amount, before tax and reclassification, of gain (loss) from derivative instrument designated and qualifying cash flow hedge included in assessment of hedge effectiveness.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 20
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- Definition

Amount, before tax, of reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Derivative Instruments and Hedging Activities (Details 3) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Derivative Instruments, Gain (Loss) [Line Items]
Recognized in accumulated other comprehensive income that were included in the assessment of effectiveness	$ (31.5)	$ (5.6)	$ (11.5)
Reclassification of losses (gains) from accumulated other comprehensive income to net income	(8.9)	10.3	6.1
Foreign Exchange Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Recognized in accumulated other comprehensive income that were included in the assessment of effectiveness	0.8	(5.4)	0.0
Foreign Exchange Contract [Member] \| Cost of Products Sold [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Reclassification of losses (gains) from accumulated other comprehensive income to net income	(1.7)	(0.9)	0.0
Foreign Exchange Contract [Member] \| Other Income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Recognized gains (losses) in consolidated statement of operations	0.0	0.1	(1.6)
Commodity Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Recognized in accumulated other comprehensive income that were included in the assessment of effectiveness	$ (32.3)	(0.2)	(11.5)
Commodity Contract [Member] \| Nickel [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Investment Contract Settlement Date Range Start	Jan. 01, 2020
Investment Contract Settlement Date Range Ending	Jun. 30, 2020
Commodity Contract [Member] \| Natural Gas [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Investment Contract Settlement Date Range Start	Jan. 01, 2020
Investment Contract Settlement Date Range Ending	Dec. 31, 2021
Gains (losses) before tax expected to be reclassified into earnings within the next twelve months	$ (10.5)
Commodity Contract [Member] \| Electricity [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Investment Contract Settlement Date Range Start	Jan. 01, 2020
Investment Contract Settlement Date Range Ending	Aug. 31, 2021
Gains (losses) before tax expected to be reclassified into earnings within the next twelve months	$ (5.8)
Commodity Contract [Member] \| Zinc [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Investment Contract Settlement Date Range Start	Jan. 01, 2020
Investment Contract Settlement Date Range Ending	Dec. 31, 2021
Gains (losses) before tax expected to be reclassified into earnings within the next twelve months	$ (3.1)
Commodity Contract [Member] \| Cost of Products Sold [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Reclassification of losses (gains) from accumulated other comprehensive income to net income	(7.2)	11.2	6.1
Recognized gains (losses) in consolidated statement of operations	$ 52.2	$ (2.4)	$ 31.6
Canada, Dollars \| Foreign Exchange Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Investment Contract Settlement Date Range Start	Jan. 01, 2020
Investment Contract Settlement Date Range Ending	Dec. 31, 2021
Gains (losses) before tax expected to be reclassified into earnings within the next twelve months	$ (1.3)