Leases - Operating Lease ROU Assets and Liabilities (Details) - USD ($) $ in Millions |
Mar. 31, 2026 |
Mar. 31, 2025 |
|---|---|---|
| Leases [Abstract] | ||
| Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration] | Other assets | Other assets |
| Operating lease ROU assets | $ 283 | $ 237 |
| Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration] | Accounts Payable and Accrued Liabilities, Current | Accounts Payable and Accrued Liabilities, Current |
| Operating lease liabilities (See Note 12) | $ 63 | $ 67 |
| Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration] | Other liabilities | Other liabilities |
| Noncurrent operating lease liabilities | $ 306 | $ 267 |
| Total operating lease liabilities | $ 369 | $ 334 |