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, 2025 |
Jun. 30, 2024 |
Mar. 31, 2025 |
|
| Financing Receivable, Allowance for Credit Loss [Roll Forward] | |||
| Beginning balance | $ 396 | $ 353 | $ 353 |
| Provision | 103 | 71 | |
| Charge-offs | (102) | (79) | |
| Recoveries | 37 | 46 | |
| Effect of translation adjustment | 1 | 0 | |
| Ending balance | 435 | 391 | 396 |
| Retail | |||
| Financing Receivable, Allowance for Credit Loss [Roll Forward] | |||
| Beginning balance | 387 | 345 | 345 |
| Provision | 103 | 71 | |
| Charge-offs | (102) | (79) | |
| Recoveries | 37 | 46 | |
| Effect of translation adjustment | 1 | 0 | |
| Ending balance | 426 | 383 | 387 |
| Dealer | |||
| Financing Receivable, Allowance for Credit Loss [Roll Forward] | |||
| Beginning balance | 9 | 8 | 8 |
| Provision | 0 | 0 | |
| Charge-offs | 0 | 0 | |
| Recoveries | 0 | 0 | |
| Effect of translation adjustment | 0 | 0 | |
| Ending balance | $ 9 | $ 8 | $ 9 |