XML 63 R53.htm IDEA: XBRL DOCUMENT
v3.23.2

Derivative Financial Instruments and Hedging (Details) € in Millions, lb in Millions, $ in Millions | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2023 USD ($) | Jun. 30, 2022 USD ($) | Jun. 30, 2023 USD ($) lb | Jun. 30, 2022 USD ($) | Jun. 30, 2023 EUR (€)
Derivative Instruments Gain Loss [Line Items] |  |  |  |  |
Percentage of estimated annual nickel requirements |  |  | 10.00% |  |
Percentage Of Forecasted Natural Gas Usage Hedged for 2023 |  |  | 80.00% |  |
Percentage Of Forecasted Natural Gas Usage Hedged for 2024 |  |  | 50.00% |  |
Percentage Of Forecasted Natural Gas Usage Hedged for 2025 |  |  | 15.00% |  |
Reclassification of Cash Flow Hedge Gain (Loss) [Abstract] |  |  |  |  |
Cash Flow Hedge Gain (Loss) To Be Reclassified Within Twelve Months |  |  | $ (2.1) |  |
Cash Flow Hedging |  |  |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |  |  |
Derivative Instruments Gain Loss Reclassified From Accumulated OCI Into Income Effective Portion Net | $ (2.9) | $ 15.5 | 1.3 | $ 19.3 |
Cash Flow Hedging | Other Comprehensive Income (Loss) [Member] |  |  |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |  |  |
Net derivative gain (loss) on hedge transactions | (1.9) | 12.3 | $ (13.3) | 31.0 |
Nickel |  |  |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |  |  |
Notional amount of nickel hedge (in pounds of nickel) | lb |  |  | 8 |  |
Interest Rate Swap | Cash Flow Hedging |  |  |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |  |  |
Derivative Instruments Gain Loss Reclassified From Accumulated OCI Into Income Effective Portion Net | 0.3 | (0.1) | $ 0.5 | (0.3) |
Interest Rate Swap | Cash Flow Hedging | Other Comprehensive Income (Loss) [Member] |  |  |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |  |  |
Net derivative gain (loss) on hedge transactions | 0.3 | 0.2 | 0.2 | 1.5 |
Nickel and other raw material contracts | Cash Flow Hedging |  |  |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |  |  |
Derivative Instruments Gain Loss Reclassified From Accumulated OCI Into Income Effective Portion Net | (1.4) | 12.1 | 3.9 | 14.5 |
Nickel and other raw material contracts | Cash Flow Hedging | Other Comprehensive Income (Loss) [Member] |  |  |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |  |  |
Net derivative gain (loss) on hedge transactions | (1.6) | 9.3 | (6.9) | 17.3 |
Natural gas contracts | Cash Flow Hedging |  |  |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |  |  |
Derivative Instruments Gain Loss Reclassified From Accumulated OCI Into Income Effective Portion Net | (1.8) | 3.4 | (3.2) | 5.0 |
Natural gas contracts | Cash Flow Hedging | Other Comprehensive Income (Loss) [Member] |  |  |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |  |  |
Net derivative gain (loss) on hedge transactions | (0.7) | 2.5 | (6.8) | 11.8 |
Foreign exchange contracts | Cash Flow Hedging |  |  |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |  |  |
Derivative Instruments Gain Loss Reclassified From Accumulated OCI Into Income Effective Portion Net | 0.0 | 0.1 | 0.1 | 0.1 |
Foreign exchange contracts | Cash Flow Hedging | Other Comprehensive Income (Loss) [Member] |  |  |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |  |  |
Net derivative gain (loss) on hedge transactions | $ 0.1 | $ 0.3 | $ 0.2 | $ 0.4 |
Designated as Hedging Instrument | Foreign exchange forward | Cash Flow Hedging |  |  |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |  |  |
Notional amount of derivative | € |  |  |  |  | € 0
2027 Term Loan |  |  |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 4.21% |  | 4.21% |  | 4.21%
2027 Term Loan | Interest Rate Swap |  |  |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |  |  |
Notional amount of derivative | $ 50.0 |  | $ 50.0 |  |

X
- Definition Percentage Of Forecasted Natural Gas Usage Hedged for Year 3 + References No definition available. + Details
Name: | ati_PercentageOfForecastedNaturalGasUsageHedgedForYear3
Namespace Prefix: | ati_
Data Type: | dtr-types1:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage Of Forecasted Natural Gas Usage Hedged for Year 1 + References No definition available. + Details
Name: | ati_PercentageOfForecastedNaturalGasUsageHedgedforYear1
Namespace Prefix: | ati_
Data Type: | dtr-types1:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Aggregate notional amount of price risk derivatives for instruments with notional amounts expressed in percentage of estimated annual domestic (U.S.) usage + References No definition available. + Details
Name: | ati_PercentageOfForecastedNaturalGasUsageHedgedforYear2
Namespace Prefix: | ati_
Data Type: | dtr-types1:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Aggregate notional amount of price risk derivatives for instruments with notional amounts expressed in percentage of annual estimated usage in production + References No definition available. + Details
Name: | ati_PercentageOfRawMaterialUsageHedged
Namespace Prefix: | ati_
Data Type: | dtr-types1:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 815 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480870/815-30-50-1 + Details
Name: | us-gaap_CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1B -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1 + Details
Name: | us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | instant

X
- 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 Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4E -Publisher FASB -URI https://asc.fasb.org//1943274/2147480434/815-10-50-4E + Details
Name: | us-gaap_DerivativeInstrumentsGainLossLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 50 -Paragraph 4D -Subparagraph (b) -SubTopic 10 -Topic 815 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480434/815-10-50-4D Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480434/815-10-50-4C + Details
Name: | us-gaap_DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Nominal mass used to calculate payments on a derivative instrument. + References No definition available. + Details
Name: | us-gaap_DerivativeNonmonetaryNotionalAmountMass
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:massItemType
Balance Type: | na
Period Type: | duration

X
- Definition Nominal or face amount used to calculate payment on derivative. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1B -Publisher FASB -URI https://asc.fasb.org//1943274/2147480434/815-10-50-1B Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1A -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480434/815-10-50-1A + Details
Name: | us-gaap_DerivativeNotionalAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | instant

X
- Definition Amount, after tax and before reclassification, of gain (loss) from 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 -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 11 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482790/220-10-45-11 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 10A -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482790/220-10-45-10A + Details
Name: | us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_ReclassificationOfCashFlowHedgeGainLossAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis=us-gaap_CashFlowHedgingMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_IncomeStatementLocationAxis=us-gaap_OtherComprehensiveIncomeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=ati_NickelMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=us-gaap_InterestRateSwapMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=ati_NickelAndOtherRawMaterialContractsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=ati_NaturalGasContractsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=us-gaap_ForeignExchangeContractMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_HedgingDesignationAxis=us-gaap_DesignatedAsHedgingInstrumentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=us-gaap_ForeignExchangeForwardMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=ati_A2027TermLoanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |