Employee Benefit Plans - Narrative (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Mar. 31, 2025 |
Mar. 31, 2024 |
Mar. 31, 2023 |
|
| Other Pension, Postretirement and Supplemental Plans | |||
| Defined Benefit Plan Disclosure [Line Items] | |||
| Employer matching contribution, percent of match (as a percent) | 6.00% | ||
| Employees’ capital accumulation plan, total expense recognized | $ 249 | $ 218 | $ 191 |
| Employees’ capital accumulation plan, company-paid contributions | $ 240 | $ 213 | $ 186 |
| Officer Medical Plan | Other Postretirement Benefits Plan | |||
| Defined Benefit Plan Disclosure [Line Items] | |||
| Weighted-average discount rate for benefit obligation (as a percent) | 5.55% | 5.20% | 4.90% |