v3.22.0.1

Debt (Details) - USD ($) |  |  |  |  |  |  |  | 2 Months Ended | 3 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Mar. 03, 2021 | May 13, 2020 | Apr. 02, 2020 | Apr. 01, 2020 | Mar. 25, 2020 | Feb. 07, 2020 | Feb. 05, 2020 | Mar. 25, 2020 | May 13, 2020 | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019 | Mar. 31, 2021 | Aug. 31, 2012
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, face amount |  |  |  |  |  |  | $ 1,200,000,000 |  |  | $ 700,000,000 | $ 700,000,000 |  |  |
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net |  |  |  |  |  |  |  |  |  | (6,000,000) | (22,000,000) |  |  |
Carrying value of long-term debt |  |  |  |  |  |  |  |  |  | 1,594,000,000 | 1,278,000,000 |  |  |
Net proceeds |  |  |  |  |  |  | 1,168,000,000 |  |  | 319,000,000 | 2,400,000,000 | $ 0 |  |
Separation transaction, payment to parent |  |  |  | $ 728,000,000 |  |  |  |  |  |  | 728,000,000 | 0 |  |
Cash |  |  |  |  |  |  | $ 500,000,000 |  |  |  |  |  | $ 60,000,000 |
Repayments of long-term debt |  |  |  |  |  |  |  |  |  | 0 | 1,100,000,000 | 0 |  |
Payment in discounts |  |  |  |  |  |  |  |  |  | 5,000,000 | 57,000,000 | $ 0 |  |
Write off from debt issuance costs |  |  |  |  |  |  |  |  |  |  | 19,000,000 |  |  |
Term Loan, Credit Facility, 2025 Notes, and ABL Credit Agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Write off from debt issuance costs |  |  |  |  |  |  |  |  | $ 19,000,000 |  |  |  |  |
Term Loan and Credit Facility |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt issuance costs |  |  |  |  | $ 30,000,000 |  |  | $ 30,000,000 |  | 14,000,000 |  |  |  |
Write off from debt issuance costs |  |  |  |  |  |  |  | 16,000,000 |  |  |  |  |  |
2025 Notes and ABL Credit Agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt issuance costs |  | $ 15,000,000 |  |  |  |  |  |  | 15,000,000 | 12,000,000 |  |  |  |
Write off from debt issuance costs |  | 3,000,000 |  |  |  |  |  |  |  |  |  |  |  |
ABL Credit Agreement | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revolving credit facility, maximum borrowing capacity |  | 800,000,000 |  |  |  |  |  |  | 800,000,000 |  |  |  |  |
Accordion feature increase limit (up to) |  | $ 350,000,000 |  |  |  |  |  |  | 350,000,000 |  |  |  |  |
ABL Credit Agreement | Revolving Credit Facility | Minimum |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revolving credit facility, commitment fee |  | 0.25% |  |  |  |  |  |  |  |  |  |  |  |
ABL Credit Agreement | Revolving Credit Facility | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revolving credit facility, commitment fee |  | 0.375% |  |  |  |  |  |  |  |  |  |  |  |
2028 Notes and Credit Agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt issuance costs |  | $ 42,000,000 |  |  |  |  |  |  | 42,000,000 |  |  |  |  |
Senior Secured Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fixed interest rate |  |  |  |  |  | 6.125% |  |  |  |  |  |  |  |
Senior Secured Notes | 2028 Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, face amount | $ 300,000,000 |  |  |  |  | $ 600,000,000 |  |  |  | 900,000,000 | $ 600,000,000 |  |  |
Fixed interest rate |  |  |  |  |  | 6.125% |  |  |  |  |  |  |  |
Net proceeds |  |  |  |  |  | $ 593,000,000 |  |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Increase (Decrease) | 106.25% |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Secured Notes | 2028 Notes | Redemption after February 14, 2023 / May 14, 2022 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt redemption percentage |  |  |  |  |  | 103.063% |  |  |  |  |  |  |  |
Senior Secured Notes | 2028 Notes | Redemption prior to February 15, 2023 / May 15, 2022 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt redemption percentage |  |  |  |  |  | 100.00% |  |  |  |  |  |  |  |
Debt redemption, additional make-whole charge |  |  |  |  |  | 1.00% |  |  |  |  |  |  |  |
Basis spread on discount rate |  |  |  |  |  | 0.50% |  |  |  |  |  |  |  |
Senior Secured Notes | 2028 Notes | Redemption prior to February 15, 2023 / May 15, 2022; limited to 40% of aggregate principal |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt redemption percentage |  |  |  |  |  | 106.125% |  |  |  |  |  |  |  |
Redemption limitation based on aggregate principal |  |  |  |  |  | 40.00% |  |  |  |  |  |  |  |
Minimum aggregate principal following redemption |  |  |  |  |  | 60.00% |  |  |  |  |  |  |  |
Maximum term allowed for redemption following offering |  |  |  |  |  | 120 days |  |  |  |  |  |  |  |
Senior Secured Notes | 2028 Notes | Redemption upon change in control |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt redemption percentage |  |  |  |  |  | 101.00% |  |  |  |  |  |  |  |
Senior Secured Notes | 2028 Notes | Minimum |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Required prior notice for debt redemption, term |  |  |  |  |  | 10 days |  |  |  |  |  |  |  |
Senior Secured Notes | 2028 Notes | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Required prior notice for debt redemption, term |  |  |  |  |  | 60 days |  |  |  |  |  |  |  |
Senior Secured Notes | 2025 Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, face amount |  | $ 700,000,000 |  |  |  |  |  |  | $ 700,000,000 |  |  |  |  |
Fixed interest rate |  | 6.00% |  |  |  |  |  |  | 6.00% |  |  |  |  |
Net proceeds |  | $ 691,000,000 |  |  |  |  |  |  |  |  |  |  |  |
Senior Secured Notes | 2025 Notes | Redemption after February 14, 2023 / May 14, 2022 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt redemption percentage |  | 103.00% |  |  |  |  |  |  |  |  |  |  |  |
Senior Secured Notes | 2025 Notes | Redemption prior to February 15, 2023 / May 15, 2022 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt redemption percentage |  | 100.00% |  |  |  |  |  |  |  |  |  |  |  |
Debt redemption, additional make-whole charge |  | 1.00% |  |  |  |  |  |  |  |  |  |  |  |
Basis spread on discount rate |  | 0.50% |  |  |  |  |  |  |  |  |  |  |  |
Senior Secured Notes | 2025 Notes | Redemption prior to February 15, 2023 / May 15, 2022; limited to 40% of aggregate principal |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt redemption percentage |  | 106.00% |  |  |  |  |  |  |  |  |  |  |  |
Redemption limitation based on aggregate principal |  | 40.00% |  |  |  |  |  |  |  |  |  |  |  |
Minimum aggregate principal following redemption |  | 60.00% |  |  |  |  |  |  |  |  |  |  |  |
Maximum term allowed for redemption following offering |  | 120 days |  |  |  |  |  |  |  |  |  |  |  |
Senior Secured Notes | 2025 Notes | Redemption upon change in control |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt redemption percentage |  | 101.00% |  |  |  |  |  |  |  |  |  |  |  |
Senior Secured Notes | 2025 Notes | Minimum |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Required prior notice for debt redemption, term |  | 10 days |  |  |  |  |  |  |  |  |  |  |  |
Senior Secured Notes | 2025 Notes | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Required prior notice for debt redemption, term |  | 60 days |  |  |  |  |  |  |  |  |  |  |  |
Term Loan |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Unamortized Premium | $ 19,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Remaining debt issuance costs | 5,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Term Loan | 2028 Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net proceeds | $ 315,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Term Loan | Term Loan |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, face amount |  |  |  |  | 600,000,000 |  |  | 600,000,000 |  |  |  |  |  |
Net proceeds |  |  |  |  | $ 575,000,000 |  |  |  |  |  |  |  |  |
Debt term (in years) |  |  |  |  | 7 years |  |  |  |  |  |  |  |  |
Repayments of long-term debt |  | $ 600,000,000 |  |  |  |  |  |  |  |  |  |  |  |
Credit Facility | Credit Facility | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, face amount |  |  |  |  | $ 1,000,000,000 |  |  | $ 1,000,000,000 |  |  |  |  |  |
Debt term (in years) |  |  |  |  | 5 years |  |  |  |  |  |  |  |  |
Proceeds from revolving credit facility |  |  | $ 500,000,000 |  |  |  |  |  |  |  |  |  |  |
Repayments of long-term debt |  | $ 500,000,000 |  |  |  |  |  |  |  |  |  |  |  |
Credit Facility | Credit Facility | Revolving Credit Facility | LIBOR |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  | 2.00% |  |  |  |  |  |  |  |  |  |  |
Credit Facility | ABL Credit Agreement | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Financial maintenance covenant, percentage of aggregate commitments |  | 10.00% |  |  |  |  |  |  |  |  |  |  |  |
Financial maintenance covenant, percentage of borrowing base |  | 10.00% |  |  |  |  |  |  |  |  |  |  |  |
Financial maintenance covenant, minimum base amount |  | $ 50,000,000 |  |  |  |  |  |  |  |  |  |  |  |
Financial maintenance covenant, term excess availability exceeds threshold |  | 30 days |  |  |  |  |  |  |  |  |  |  |  |
Required fixed charge coverage ratio |  | 1.00 |  |  |  |  |  |  |  |  |  |  |  |
Agent control of cash, percentage of aggregate commitments |  | 12.50% |  |  |  |  |  |  |  |  |  |  |  |
Agent control of cash, percentage of borrowing base |  | 12.50% |  |  |  |  |  |  |  |  |  |  |  |
Agent control of cash, minimum base amount |  | $ 62,500,000 |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Unused Borrowing Capacity, Amount |  |  |  |  |  |  |  |  |  | $ 790,000,000 |  |  |  |
Credit Facility | ABL Credit Agreement | Revolving Credit Facility | Minimum |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Agent control of cash, term excess availability exceeds threshold |  | 5 days |  |  |  |  |  |  |  |  |  |  |  |
Credit Facility | ABL Credit Agreement | Revolving Credit Facility | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Agent control of cash, term excess availability exceeds threshold |  | 30 days |  |  |  |  |  |  |  |  |  |  |  |
Credit Facility | ABL Credit Agreement | Revolving Credit Facility | Fed funds effective rate and overnight bank funding rate |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  | 0.50% |  |  |  |  |  |  |  |  |  |  |  |
Credit Facility | ABL Credit Agreement | Revolving Credit Facility | LIBOR |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  | 1.00% |  |  |  |  |  |  |  |  |  |  |  |
Applicable margin |  | 2.25% |  |  |  |  |  |  | 2.25% |  |  |  |  |
Credit Facility | ABL Credit Agreement | Revolving Credit Facility | LIBOR | Minimum |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fixed interest rate |  | 0.75% |  |  |  |  |  |  | 0.75% |  |  |  |  |
Applicable margin |  | 1.75% |  |  |  |  |  |  | 1.75% |  |  |  |  |
Credit Facility | ABL Credit Agreement | Revolving Credit Facility | LIBOR | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Applicable margin |  | 2.25% |  |  |  |  |  |  | 2.25% |  |  |  |  |
Credit Facility | ABL Credit Agreement | Revolving Credit Facility | Base Rate |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Applicable margin |  | 1.25% |  |  |  |  |  |  | 1.25% |  |  |  |  |
Credit Facility | ABL Credit Agreement | Revolving Credit Facility | Base Rate | Minimum |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Applicable margin |  | 0.75% |  |  |  |  |  |  | 0.75% |  |  |  |  |
Credit Facility | ABL Credit Agreement | Revolving Credit Facility | Base Rate | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Applicable margin |  | 1.25% |  |  |  |  |  |  | 1.25% |  |  |  |  |
Bonds | Midwestern Disaster Area Revenue Bonds Series 2012 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, face amount |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 250,000,000

X
- Definition Debt Covenant, Agent Control of Cash, Minimum Base Amount + References No definition available. + Details
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Namespace Prefix: | arnc_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

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- Definition Debt Covenant, Agent Control of Cash, Percentage of Aggregate Commitments + References No definition available. + Details
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X
- Definition Debt Covenant, Agent Control of Cash, Percentage of Borrowing Base + References No definition available. + Details
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- Definition Debt Covenant, Agent Control of Cash, Term Excess Availability Exceeds Threshold + References No definition available. + Details
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- Definition Debt Covenant, Financial Maintenance Covenant, Minimum Base Amount + References No definition available. + Details
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Namespace Prefix: | arnc_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

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- Definition Debt Covenant, Financial Maintenance Covenant, Percentage of Aggregate Commitments + References No definition available. + Details
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- Definition Debt Covenant, Financial Maintenance Covenant, Percentage of Borrowing Base + References No definition available. + Details
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Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

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- Definition Debt Covenant, Financial Maintenance Covenant, Term Excess Availability Exceeds Threshold + References No definition available. + Details
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Namespace Prefix: | arnc_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

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- Definition Debt Instrument, Notice for Debt Redemption, Term + References No definition available. + Details
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Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

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- Definition Debt Instrument, Redemption, Additional Make-Whole Redemption Charge + References No definition available. + Details
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- Definition Debt Instrument, Redemption, Basis Spread on Discount Rate + References No definition available. + Details
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Namespace Prefix: | arnc_
Data Type: | dtr-types:percentItemType
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- Definition Debt Instrument, Redemption, Limitation Based on Aggregate Principal + References No definition available. + Details
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Data Type: | dtr-types:percentItemType
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- Definition Debt Instrument, Redemption, Maximum Term Following Offering + References No definition available. + Details
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Namespace Prefix: | arnc_
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Balance Type: | na
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- Definition Debt Instrument, Redemption, Minimum Aggregate Principal Following Redemption + References No definition available. + Details
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Namespace Prefix: | arnc_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

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- Definition Fixed Charge Coverage Ratio + References No definition available. + Details
Name: | arnc_FixedChargeCoverageRatio
Namespace Prefix: | arnc_
Data Type: | xbrli:pureItemType
Balance Type: | na
Period Type: | duration

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- Definition Line Of Credit Facility, Accordion Feature, Increase Limit + References No definition available. + Details
Name: | arnc_LineOfCreditFacilityAccordionFeatureIncreaseLimit
Namespace Prefix: | arnc_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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- Definition Payments for Separation Transaction + References No definition available. + Details
Name: | arnc_PaymentsForSeparationTransaction
Namespace Prefix: | arnc_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
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