Supplemental Balance Sheet Information - Narrative (Details) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | |
|---|---|---|---|
Mar. 31, 2026 |
Mar. 31, 2025 |
Sep. 30, 2025 |
|
| Organization, Consolidation and Presentation of Financial Statements [Abstract] | |||
| Unpaid capital expenditures | $ 17 | $ 12 | $ 33 |