Employee benefit plans - Projected benefit obligation, accumulated benefit obligation and fair value of plan assets for pension plans with ABO and PBO in excess of plan assets (Detail) - JPY (¥) ¥ in Millions |
Mar. 31, 2026 |
Mar. 31, 2025 |
|---|---|---|
| Plans with ABO in excess of plan assets: | ||
| PBO | ¥ 45,356 | ¥ 45,064 |
| ABO | 45,356 | 45,064 |
| Fair value of plan assets | ||
| Plans with PBO in excess of plan assets: | ||
| PBO | 45,356 | 45,064 |
| ABO | 45,356 | 45,064 |
| Fair value of plan assets |
| X | ||||||||||
- Definition Amount of accumulated benefit obligation for defined benefit pension plan with projected benefit obligation in excess of plan assets. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of plan asset for defined benefit pension plan with projected benefit obligation in excess of plan assets. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of projected benefit obligation for defined benefit pension plan with projected benefit obligation in excess of plan assets. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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| X | ||||||||||
- References No definition available.
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| X | ||||||||||
- Definition Amount of accumulated benefit obligation for defined benefit plan with accumulated benefit obligation in excess of plan assets. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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| X | ||||||||||
- Definition Amount of plan asset for defined benefit plan with accumulated benefit obligation in excess of plan assets. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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| X | ||||||||||
- Definition Amount of projected benefit obligation for defined benefit pension plan with accumulated benefit obligation in excess of plan assets. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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| X | ||||||||||
- References No definition available.
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