Basis of Presentation and New Accounting Standards - Schedule of Restructuring and Other Operating Expense (Details) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | |||
|---|---|---|---|---|---|
Sep. 29, 2025 |
Dec. 28, 2025 |
Sep. 29, 2025 |
Dec. 29, 2024 |
Dec. 29, 2024 |
|
| Accounting Policies [Abstract] | |||||
| Restructuring and other exit costs | $ 0.0 | $ 9.6 | $ 3.7 | $ 156.7 | $ 209.5 |
| Executive severance costs | 0.0 | 0.0 | 1.4 | 1.4 | |
| Project, transformation and transaction costs | 0.0 | 14.1 | 13.8 | 7.8 | 13.8 |
| Amortization or impairment of fresh start accounting and acquisition-related intangibles | 0.0 | 4.0 | 0.0 | 0.3 | 0.6 |
| Other | 0.0 | 0.5 | 2.9 | 2.1 | 4.1 |
| Restructuring and other expenses | $ 0.0 | $ 28.2 | $ 20.4 | $ 168.3 | $ 229.4 |