Operating Segment and Revenue Information - Narrative (Details) - JPY (¥) ¥ in Millions |
12 Months Ended | ||
|---|---|---|---|
Mar. 31, 2026 |
Mar. 31, 2025 |
Mar. 31, 2024 |
|
| Disclosure of major customers [line items] | |||
| Revenue from contracts with customers | ¥ 4,505,720 | ¥ 4,581,551 | ¥ 4,263,762 |
| Revenue that was included in contract liability balance at beginning of period | 22,532 | 5,634 | 5,526 |
| Revenue from performance obligations satisfied or partially satisfied in previous periods | 108,267 | 97,560 | 80,794 |
| Cencora Group | Customer risk concentration, net sales | |||
| Disclosure of major customers [line items] | |||
| Revenue from contracts with customers | 470,295 | 577,017 | 579,065 |
| McKesson Group | Customer risk concentration, net sales | |||
| Disclosure of major customers [line items] | |||
| Revenue from contracts with customers | ¥ 539,890 | ¥ 592,323 | 578,767 |
| Cardinal Health Group | Customer risk concentration, net sales | |||
| Disclosure of major customers [line items] | |||
| Revenue from contracts with customers | ¥ 436,951 | ||