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.

+ Details

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226016-175313

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=d3e41678-113959

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (d)(2)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

+ Details

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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.

+ Details

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- Definition

Nominal number of units used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959

+ Details

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Period Type:	instant

- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

+ Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Derivative Instruments and Hedging Activities (Details) € in Millions, $ in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2019 USD ($) MMBTU MW t lb	Dec. 31, 2019 CAD ($) MMBTU MW t lb	Dec. 31, 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] \| Nickel [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount \| lb	150,000	150,000	150,000	0	0
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 [Line Items]
Derivative, Nonmonetary Notional Amount \| MMBTU	37,708,000	37,708,000	37,708,000	39,868,000	39,868,000
Investment Contract Settlement Date Range Start	Jan. 01, 2020
Investment Contract Settlement Date Range Ending	Dec. 31, 2021
Commodity Contract [Member] \| Zinc [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount \| lb	35,550,000	35,550,000	35,550,000	52,150,000	52,150,000
Investment Contract Settlement Date Range Start	Jan. 01, 2020
Investment Contract Settlement Date Range Ending	Dec. 31, 2021
Commodity Contract [Member] \| Iron Ore [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount \| t	1,495,000	1,495,000	1,495,000	2,125,000	2,125,000
Investment Contract Settlement Date Range Start	Jan. 01, 2020
Investment Contract Settlement Date Range Ending	Jun. 30, 2021
Commodity Contract [Member] \| Electricity [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount \| MW	1,683,000	1,683,000	1,683,000	1,461,000	1,461,000
Investment Contract Settlement Date Range Start	Jan. 01, 2020
Investment Contract Settlement Date Range Ending	Aug. 31, 2021
Foreign Exchange Contract [Member] \| Euro Member Countries, Euro
Derivative [Line Items]
Derivative, Notional Amount \| €			€ 1.5		€ 4.0
Investment Contract Settlement Date Range Start	Jan. 01, 2020
Investment Contract Settlement Date Range Ending	Jan. 31, 2020
Foreign Exchange Contract [Member] \| Canada, Dollars
Derivative [Line Items]
Derivative, Notional Amount \| $		$ 72.6		$ 118.6
Investment Contract Settlement Date Range Start	Jan. 01, 2020
Investment Contract Settlement Date Range Ending	Dec. 31, 2021