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Retirement Benefits (Details 17) - Pension Benefits [Member] - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Multiemployer Plan Disclosure [Line Items] |  |  |  |
Company Contributions |  | $ 4.0 | $ 4.8 | $ 5.6
Steelworkers Western Independent Shops Pension Plan [Member] |  |  |  |
Multiemployer Plan Disclosure [Line Items] |  |  |  |
Pension Plan Number |  | 001 |  |
Multiemployer Plan, Pension, Insignificant, Employer Identification Number |  | 900169564 |  |
Pension Protection Act Zone Status | [1] | Green | Green |
FIP / RP Status Pending / Implemented | [2] | NA |  |
Company Contributions |  | $ 0.1 | $ 0.7 | 0.9
Surcharge Imposed | [3] | No |  |
Expiration Dates of Collective Bargaining Agreements |  | Feb. 28, 2025 |  |
Boilermakers-Blacksmiths National Pension Trust [Member] |  |  |  |
Multiemployer Plan Disclosure [Line Items] |  |  |  |
Pension Plan Number |  | 001 |  |
Multiemployer Plan, Pension, Insignificant, Employer Identification Number |  | 486168020 |  |
Pension Protection Act Zone Status | [1] | Yellow | Yellow |
FIP / RP Status Pending / Implemented | [2] | Implemented |  |
Company Contributions |  | $ 2.0 | $ 2.1 | 2.5
Surcharge Imposed | [3] | No |  |
Expiration Dates of Collective Bargaining Agreements |  | Sep. 30, 2026 |  |
IAM National Pension Fund [Member] |  |  |  |
Multiemployer Plan Disclosure [Line Items] |  |  |  |
Pension Plan Number |  | 002 |  |
Multiemployer Plan, Pension, Insignificant, Employer Identification Number |  | 516031295 |  |
Pension Protection Act Zone Status | [1] | Red | Red |
FIP / RP Status Pending / Implemented | [2] | Implemented |  |
Company Contributions |  | $ 1.9 | $ 2.0 | $ 2.2
Surcharge Imposed | [3] | Yes |  |
IAM National Pension Fund [Member] | Minimum |  |  |  |
Multiemployer Plan Disclosure [Line Items] |  |  |  |
Expiration Dates of Collective Bargaining Agreements | [4] | Feb. 27, 2022 |  |
IAM National Pension Fund [Member] | Maximum |  |  |  |
Multiemployer Plan Disclosure [Line Items] |  |  |  |
Expiration Dates of Collective Bargaining Agreements | [4] | Nov. 13, 2023 |  |
[1] | The most recent Pension Protection Act Zone Status is based on information provided to ATI and other participating employers by each plan, as certified by the plan’s actuary. A plan in the “deep red” zone had been determined to be in “critical and declining status”, based on criteria established by the Internal Revenue Code (Code), and is in critical status (as defined by the “red” zone) and is projected to become insolvent (run out of money to pay benefits) within 15 years (or within 20 years if a special rule applies). A plan in the “red” zone had been determined to be in “critical status”, based on criteria established by the Code, and is generally less than 65% funded. A plan in the “yellow” zone has been determined to be in “endangered status”, based on criteria established under the Code, and is generally less than 80% funded. A plan in the “green” zone has been determined to be neither in “critical status” nor in “endangered status”, and is generally at least 80% funded. Additionally, a plan may voluntarily place itself into a rehabilitation plan. In April 2019, the Company received notification from the IAM National Pension Fund (IAM Fund) that its’ actuary certified the IAM Fund as “endangered status” for the plan year beginning January 1, 2019, and that the IAM Fund was voluntarily placing itself in “red” zone status and implementing a rehabilitation plan. In April 2020 and 2021, the Company received notification from the IAM Fund that it was certified by its actuary as being in “red” zone status for the plan years beginning January 1, 2020 and 2021. A 5% contribution surcharge was imposed as of June 1, 2019 for the rest of 2019, increasing to a 10% surcharge rate beginning January 1, 2020 in addition to the contribution rate specified in the applicable collective bargaining agreements. The contribution surcharge ends when an employer begins contributing under a collective bargaining agreement that includes terms consistent with the rehabilitation plan. In April 2019, the Company received notifications from the Boilermakers-Blacksmiths National Pension Trust (Blacksmiths Trust) that it was certified by its actuary as being in “red” zone status for the plan year beginning January 1, 2019. A rehabilitation plan has been adopted for the Blacksmiths Trust, and the Company and the Blacksmiths union agreed to adopt the rehabilitation plan in 2019 prior to a contribution surcharge being imposed. In April 2020 and 2021, the funding status improved for the Blacksmiths Trust as it was certified by its actuary as being in the “yellow” zone for the plan years beginning January 1, 2020 and 2021.
[2] | The “FIP / RP Status Pending / Implemented” column indicates whether a Funding Improvement Plan, as required under the Code by plans in the “yellow” zone, or a Rehabilitation Plan, as required under the Code to be adopted by plans in the “red” or “deep red” zones, is pending or has been implemented as of the end of the plan year that ended in 2021.
[3] | The “Surcharge Imposed” column indicates whether ATI’s contribution rate for 2021 included an amount in addition to the contribution rate specified in the applicable collective bargaining agreement, as imposed by a plan in “critical status” or “critical and declining status”, in accordance with the requirements of the Code.
[4] | The Company is party to five separate bargaining agreements that require contributions to this plan. Expiration dates of these collective bargaining agreements range between February 27, 2022 and November 13, 2023.

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