Retirement Benefits - Movements in Fair Value of the Plan Assets (Detail) - JPY (¥) ¥ in Millions |
12 Months Ended | ||
|---|---|---|---|
Mar. 31, 2026 |
Mar. 31, 2025 |
Mar. 31, 2024 |
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| Disclosure of net defined benefit liability (asset) [Line Items] | |||
| At beginning of period | ¥ (443,867) | ¥ (330,739) | |
| Interest income | (11,064) | (7,356) | ¥ (6,213) |
| At end of period | (659,730) | (443,867) | (330,739) |
| Plan assets [member] | |||
| Disclosure of net defined benefit liability (asset) [Line Items] | |||
| At beginning of period | 1,804,994 | 1,820,599 | |
| Interest income | 41,293 | 27,406 | |
| Return on plan assets excluding interest income | 217,483 | (13,129) | |
| Contributions by employer | 13,384 | 13,979 | |
| Benefits paid | (45,227) | (43,583) | |
| Others | 2,759 | (278) | |
| At end of period | ¥ 2,034,686 | ¥ 1,804,994 | ¥ 1,820,599 |
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- Definition The decrease (increase) in net defined benefit liability (asset) resulting from contributions to a defined benefit plan by the employer. [Refer: Net defined benefit liability (asset); Defined benefit plans [domain]] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table. No definition available.
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- Definition The increase (decrease) in the net defined benefit liability (asset) resulting from changes that the entity does not separately disclose in the same statement or note. [Refer: Net defined benefit liability (asset)] Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- References Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The amount of deficit or surplus in a defined benefit plan, adjusted for any effect of limiting a net defined benefit asset to the asset ceiling. [Refer: Defined benefit plans [domain]] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The decrease (increase) in the net defined benefit liability (asset) resulting from payments from the plan. [Refer: Net defined benefit liability (asset)] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The decrease (increase) in the net defined benefit liability (asset) resulting from the return on plan assets, excluding amounts included in interest income or expense. The return on plan assets is interest, dividends and other revenue derived from the plan assets, together with realised and unrealised gains or losses on the plan assets, less any costs of managing plan assets and less any tax payable by the plan itself, other than tax included in the actuarial assumptions used to measure the present value of the defined benefit obligation. [Refer: Plan assets [member]; Net defined benefit liability (asset); Actuarial assumptions [domain]; Increase (decrease) in net defined benefit liability (asset) resulting from interest expense (income)] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Details
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