Finance Receivables - Summary of Activity in Allowance for Credit Losses of Finance Receivables (Detail) - USD ($) $ in Millions |
3 Months Ended | 12 Months Ended | |
|---|---|---|---|
Jun. 30, 2026 |
Jun. 30, 2025 |
Mar. 31, 2026 |
|
| Financing Receivable, Allowance for Credit Loss [Roll Forward] | |||
| Beginning balance | $ 436 | $ 396 | $ 396 |
| Provision | 86 | 103 | |
| Charge-offs | (113) | (102) | |
| Recoveries | 41 | 37 | |
| Effect of translation adjustment | 0 | 1 | |
| Ending balance | 450 | 435 | 436 |
| Retail | |||
| Financing Receivable, Allowance for Credit Loss [Roll Forward] | |||
| Beginning balance | 427 | 387 | 387 |
| Provision | 86 | 103 | |
| Charge-offs | (113) | (102) | |
| Recoveries | 41 | 37 | |
| Effect of translation adjustment | 0 | 1 | |
| Ending balance | 441 | 426 | 427 |
| Dealer | |||
| Financing Receivable, Allowance for Credit Loss [Roll Forward] | |||
| Beginning balance | 9 | 9 | 9 |
| Provision | 0 | 0 | |
| Charge-offs | 0 | 0 | |
| Recoveries | 0 | 0 | |
| Effect of translation adjustment | 0 | 0 | |
| Ending balance | $ 9 | $ 9 | $ 9 |