Retirement Benefits - Movements in Defined Benefit Obligation (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 | |
| Current service cost | (21,924) | (25,597) | ¥ (26,431) |
| Interest cost | 11,064 | 7,356 | 6,213 |
| Past service cost | 462 | (20) | |
| At end of period | 659,730 | 443,867 | 330,739 |
| Present value of defined benefit obligation [member] | |||
| Disclosure of net defined benefit liability (asset) [Line Items] | |||
| At beginning of period | 883,055 | 986,810 | |
| Current service cost | 21,924 | 25,597 | |
| Interest cost | 20,286 | 15,154 | |
| Actuarial losses (gains)—demographic assumptions | 567 | (4,170) | |
| Actuarial losses (gains)—financial assumptions | (81,664) | (80,455) | |
| Actuarial losses (gains)—experience | (3,837) | 447 | |
| Benefits paid | (45,227) | (43,583) | |
| Lump-sum payments | (15,623) | (16,094) | |
| Past service cost | 462 | ||
| Others | 1,541 | (651) | |
| At end of period | ¥ 781,484 | ¥ 883,055 | ¥ 986,810 |
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- Definition The decrease (increase) in a net defined benefit liability (asset) resulting from actuarial gains (losses) arising from changes in demographic assumptions that result in remeasurements of the net defined benefit liability (asset). Demographic assumptions deal with matters such as: (a) mortality; (b) rates of employee turnover, disability and early retirement; (c) the proportion of plan members with dependants who will be eligible for benefits; (d) the proportion of plan members who will select each form of payment option available under the plan terms; and (e) claim rates under medical plans. [Refer: Net defined benefit liability (asset)] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The decrease (increase) in a net defined benefit liability (asset) resulting from actuarial gains (losses) arising from changes in financial assumptions that result in remeasurements of the net defined benefit liability (asset). Financial assumptions deal with items such as: (a) the discount rate; (b) benefit levels, excluding any cost of the benefits to be met by employees, and future salary; (c) in the case of medical benefits, future medical costs, including claim handling costs (ie the costs that will be incurred in processing and resolving claims, including legal and adjuster's fees); and (d) taxes payable by the plan on contributions relating to service before the reporting date or on benefits resulting from that service. [Refer: Net defined benefit liability (asset)] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The decrease (increase) in a net defined benefit liability (asset) resulting from actuarial gains (losses) arising from experience adjustments that result in remeasurements of the net defined benefit liability (asset). Experience adjustments deal with the effects of differences between the previous actuarial assumptions and what has actually occurred. [Refer: Net defined benefit liability (asset)] Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition The increase (decrease) in the net defined benefit liability (asset) resulting from employee service in the current period. [Refer: Net defined benefit liability (asset)] 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 increase (decrease) in the net defined benefit liability (asset) resulting from past service cost. Past service cost is the change in the present value of the defined benefit obligation for employee service in prior periods, resulting from a plan amendment (the introduction or withdrawal of, or changes to, a defined benefit plan) or a curtailment (a significant reduction by the entity in the number of employees covered by a plan). [Refer: Net defined benefit liability (asset); 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 lump-sum payments. No definition available.
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- Details
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