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v3.25.2

Per Share Information (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 29, 2025 | Jun. 30, 2024 | Jun. 29, 2025 | Jun. 30, 2024 | Sep. 03, 2024
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] |  |  |  |  |
Net income attributable to ATI | $ 100.7 | $ 81.9 | $ 197.7 | $ 148.0 |
Net income attributable to ATI after assumed conversions | $ 100.7 | $ 84.1 | $ 197.7 | $ 152.3 |
Denominator for basic net income per common share – weighted average shares | 139,800 | 124,400 | 140,700 | 125,300 |
Share-based compensation | 3,300 | 3,100 | 3,000 | 2,800 |
Denominator for diluted net income per common share – adjusted weighted average shares and assumed conversions | 143,100 | 146,300 | 143,700 | 146,900 |
Basic net income attributable to ATI per common share (in dollars per share) | $ 0.72 | $ 0.66 | $ 1.40 | $ 1.18 |
Diluted net income attributable to ATI per common share (in dollars per share) | $ 0.70 | $ 0.58 | $ 1.38 | $ 1.04 |
Antidilutive Securities Excluded from Computation of Earnings Per Share Amount | 0 | 0 | 0 | 0 |
Purchase of treasury stock | $ (250.0) |  | $ (320.0) | $ (150.0) |
Stock repurchase plan, authorized amount |  |  |  |  | $ 700.0
Treasury Stock, Shares, Acquired | 3,200 |  | 4,400 | 3,400 |
Share Repurchase Program, Utilized, Amount | $ 430.0 |  | $ 430.0 |  |
Purchase of treasury stock | (252.6) | $ 0.0 | (322.8) | $ (151.2) |
3.5% Convertible Senior Notes due 2025 |  |  |  |  |
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] |  |  |  |  |
Convertible Senior Notes- Effect on numerator | $ 0.0 | $ 2.2 | $ 0.0 | $ 4.3 |
Convertible Senior Notes- Effect on denominator | 0 | 18,800 | 0 | 18,800 |
3.5% Convertible Senior Notes due 2025 | Convertible Debt |  |  |  |  |
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] |  |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage |  | 3.50% |  | 3.50% |
Interest rate |  | 3.50% |  | 3.50% |
Treasury Stock |  |  |  |  |
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] |  |  |  |  |
Purchase of treasury stock | $ (252.6) | $ 0.0 | $ (322.8) | $ (151.2) |

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