Trade Accounts and Other Receivables - Summary of Changes in the Allowance for Doubtful Accounts (Detail) - JPY (¥) ¥ in Millions |
12 Months Ended | |
|---|---|---|
Mar. 31, 2026 |
Mar. 31, 2025 |
|
| Text block 1 [Abstract] | ||
| Allowance for doubtful accounts at beginning of year | ¥ 127,296 | ¥ 122,105 |
| Provision for doubtful accounts, net of reversal | 8,060 | 9,835 |
| Write-offs | (9,646) | (3,128) |
| Other | (7,850) | (1,516) |
| Allowance for doubtful accounts at end of year | ¥ 117,860 | ¥ 127,296 |