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v3.23.2

Fair Value Measurements - Level 3 Reconciliation (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2022 | Jun. 30, 2023 | Jun. 30, 2022
LME forward financial sales contracts |  |  |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward] |  |  |
Balance, beginning | $ 0.0 | $ 1.8 | $ 0.0
Total realized/unrealized gains (losses) |  |  |
Included in net income | 0.0 |  | 0.0
Transfers into Level 3 | 1.6 |  | 1.6
Transfers out of Level 3 |  | (1.8) | 0.0
Balance, ending | 1.6 | 0.0 | 1.6
Change in unrealized gains (losses) | 0.0 | 0.0 | 0.0
LME forward financial sales contracts |  |  |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward] |  |  |
Balance, beginning | (16.7) | (4.6) | (5.1)
Total realized/unrealized gains (losses) |  |  |
Included in net income | 12.9 |  | 3.8
Transfers into Level 3 | 0.0 |  | (2.5)
Transfers out of Level 3 |  | 4.6 | 0.0
Balance, ending | (3.8) | 0.0 | (3.8)
Change in unrealized gains (losses) | 12.9 | $ 0.0 | 3.8
Casthouse currency hedges |  |  |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward] |  |  |
Balance, beginning | 0.0 |  | 0.0
Total realized/unrealized gains (losses) |  |  |
Included in net income | 0.0 |  | 0.0
Transfers into Level 3 | (0.0) |  | 0.0
Transfers out of Level 3 |  |  | 0.0
Balance, ending | 0.0 |  | 0.0
Change in unrealized gains (losses) | 0.0 |  | 0.0
Nord Pool Swaps |  |  |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward] |  |  |
Balance, beginning |  |  | 0.2
Total realized/unrealized gains (losses) |  |  |
Included in net income |  |  | 0.0
Transfers into Level 3 |  |  | 0.0
Transfers out of Level 3 |  |  | (0.2)
Balance, ending | 0.0 |  | 0.0
Change in unrealized gains (losses) |  |  | 0.0
FX Swaps |  |  |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward] |  |  |
Balance, beginning |  |  | (0.2)
Total realized/unrealized gains (losses) |  |  |
Included in net income |  |  | 0.0
Transfers into Level 3 |  |  | 0.0
Transfers out of Level 3 |  |  | 0.2
Balance, ending | $ 0.0 |  | 0.0
Change in unrealized gains (losses) |  |  | $ 0.0

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- Definition Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Total Realized/Unrealized Gains (Losses) [Abstract] + References No definition available. + Details
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- Definition Amount of gain (loss) recognized in income from derivative asset (liability) after deduction of derivative liability (asset), measured at fair value on recurring basis using unobservable input (level 3). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-3 + Details
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