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Retirement and Postretirement Plans - Narrative (Details) - USD ($) |  | 1 Months Ended | 3 Months Ended | 9 Months Ended
--- | --- | --- | --- | ---
Oct. 03, 2025 | Oct. 31, 2025 | Oct. 29, 2021 | Sep. 30, 2025 | Mar. 31, 2025 | Sep. 30, 2024 | Jun. 30, 2024 | Mar. 31, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |  |  |  |  |
Loss (gain) from remeasurement of benefit plans |  |  |  | $ 0 |  | $ 0 | $ 1,000,000 |  | $ 0 | $ 1,800,000
Investment losses on plan assets |  |  |  |  |  |  | 1,800,000 |  |  |
Offset amount in the decrease of liability |  |  |  |  |  |  | 700,000 |  |  |
Gain on plan asset annuitization |  |  |  |  |  |  | $ 100,000 |  |  |
Subsequent Event |  |  |  |  |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |  |  |  |  |
Defined benefit plan term of contract | 4 years |  |  |  |  |  |  |  |  |
Salaried Plan |  |  |  |  |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |  |  |  |  |
Benefit plan terminated effective date |  |  |  |  |  |  |  |  | Mar. 31, 2022 |
Defined benefit plan of recognized loss |  |  |  |  | $ 3,600,000 |  |  |  |  |
Loss (gain) from remeasurement of benefit plans |  |  |  |  |  |  |  | $ 800,000 |  |
Bargaining Plan |  |  |  |  |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |  |  |  |  |
Defined benefit plan term of contract |  |  | 4 years |  |  |  |  |  |  |
Company contributions to plans |  | $ 62,000,000 |  | $ 0 |  |  |  |  |  |
Bargaining Plan | Subsequent Event |  |  |  |  |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |  |  |  |  |
Additional contributions expected to be made during remainder of fiscal year |  | $ 3,500,000 |  |  |  |  |  |  |  |
Pension | United States of America | Salaried Plan |  |  |  |  |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |  |  |  |  |
Defined benefit plan annuitization settlement |  |  |  |  |  |  |  |  | $ 121,000,000 |

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