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Restructuring - Additional Information (Details) - USD ($) | 3 Months Ended | 9 Months Ended
--- | --- | ---
Jun. 30, 2026 | Mar. 31, 2026 | Dec. 31, 2025 | Jun. 30, 2025 | Jun. 30, 2026 | Jun. 30, 2025
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Total charges | $ 42,000,000 | $ 8,000,000 | $ 7,000,000 | $ 3,000,000 | $ 57,000,000 | $ 6,000,000
Cash payment for restructuring | 9,000,000 | $ 2,000,000 | 4,000,000 |  |  |
2026 PC Plan [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Estimated severance costs and asset impairments | 6,000,000 |  |  |  | 19,000,000 |
Cash payment for restructuring | 1,000,000 |  |  |  | 1,000,000 |
2026 PC Plan [Member] | Remainder of Fiscal 2026 [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Expected additional restructuring charges |  |  |  |  | 7,000,000 |
Cash payment for restructuring |  |  |  |  | 3,000,000 |
2026 PC Plan [Member] | Fiscal 2027 [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Expected additional restructuring charges |  |  |  |  | 7,000,000 |
Cash payment for restructuring |  |  |  |  | 6,000,000 |
2026 PC Plan [Member] | Thereafter [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Cash payment for restructuring |  |  |  |  | 1,000,000 |
2025 Reorganizations [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Severance costs |  |  | $ 9,000,000 |  |  |
Additional restructuring charges |  |  |  |  | 0 |
2025 Reorganizations [Member] | Remainder of Fiscal 2026 [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Cash payment for restructuring |  |  |  |  | 7,000,000 |
RM Plan [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Estimated severance costs, asset impairments, and accelerated depreciation | 36,000,000 |  |  |  | 38,000,000 |
Cash payment for restructuring | $ 6,000,000 |  |  |  | 6,000,000 |
RM Plan [Member] | Remainder of Fiscal 2026 [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Expected additional restructuring charges |  |  |  |  | 8,000,000 |
Cash payment for restructuring |  |  |  |  | 2,000,000 |
RM Plan [Member] | Fiscal 2027 [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Expected additional restructuring charges |  |  |  |  | 14,000,000 |
Cash payment for restructuring |  |  |  |  | 9,000,000 |
RM Plan [Member] | Accelerated Depreciation and Site Demolition and Other Related Costs [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Expected additional restructuring charges |  |  |  |  | $ 22,000,000 |

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