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)
-Number 210
-Article 12
-Section 13
-Sentence Column B

+ Details

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- Definition

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
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

+ 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.

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- Definition

The percentage of expected requirements covered by the aggregate notional amount of derivative contracts expressed in nonmonetary units. For example, the number of barrels specified in a fuel oil forward purchase contract as a percentage of expected need.

+ References

No definition available.

+ Details

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Derivatives, Hedging Programs and Other Financial Instruments, Material Derivative Positions (Details) mmlbs in Millions	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Sep. 30, 2018 EUR (€) MMBTU MWH mmlbs
Aluminum \| Designated as Hedging Instrument \| Purchase
Derivative [Line Items]
Derivative non-monetary notional amount					138.3
Aluminum \| Designated as Hedging Instrument \| Sales
Derivative [Line Items]
Derivative non-monetary notional amount					2.1
Midwest premium swap contracts \| Designated as Hedging Instrument \| Purchase
Derivative [Line Items]
Derivative non-monetary notional amount					105.9
Alloy Metal Hedge \| Designated as Hedging Instrument \| Purchase
Derivative [Line Items]
Derivative non-monetary notional amount					9.9
Natural Gas \| Designated as Hedging Instrument \| Purchase
Derivative [Line Items]
Derivative non-monetary notional amount \| MMBTU					4,130,000
Electricity \| Designated as Hedging Instrument \| Purchase
Derivative [Line Items]
Derivative non-monetary notional amount \| MWH					219,600
Foreign Exchange Contract \| Designated as Hedging Instrument \| Purchase
Derivative [Line Items]
Derivative notional amount \| €					€ 33,064
Scenario, Forecast \| Natural Gas
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount, Percent of Required Need, Coverage	63.00%	67.00%	68.00%	70.00%
Scenario, Forecast \| Electricity
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount, Percent of Required Need, Coverage	9.00%	54.00%	54.00%	53.00%