Average remaining service period of active participants in PnYnMnDTnHnMnS format.

No definition available.

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- Definition

Contributions to overseas defined contribution pension plans

+ References

No definition available.

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- Definition

The amount of health care benefit costs which are equivalent to the required contribution for the period. The cost of retiree health care benefits are not covered through retiree contributions but not reserved for the future cost.

+ References

No definition available.

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- Definition

Defined Benefit Plan Unrealized and Realized Gains / Loss

+ References

No definition available.

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- Definition

Number of years required to entitle payments upon termination.

+ References

No definition available.

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- Definition

Pension Plans, Postretirement and Other Employee Benefits [Line Items]

+ References

No definition available.

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- Definition

Percentage of gains and losses relates to benefit obligation and fair value of plan assets.

+ References

No definition available.

+ Details

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- Definition

Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level.

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- Definition

Amount of asset, recognized in statement of financial position, for overfunded defined benefit pension and other postretirement plans.

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- Definition

Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

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- Definition

Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

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- Definition

Amount of cost (reversal of cost) for pension benefits. Excludes other postretirement benefits.

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Employee benefit plans - Additional information (Detail) - JPY (¥) ¥ in Millions	12 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Mar. 31, 2024
Pension plans, postretirement and other employee benefits [Line items]
Number of years required for payment	2 years
Excess percentage of the greater of the projected benefit obligation or the fair value of plan assets	10.00%
Average remaining service period of active participants	12 years
Accumulated benefit obligation	¥ 198,294	¥ 218,187
Fair value of plan assets	202,368	208,523	¥ 219,869
Contributions to the defined contribution pension plans	7,049	6,681	6,656
Contributions to overseas defined contribution pension plans	21,674	15,179	15,026
Health care benefit cost	10,146	10,066	9,453
Level 1 [Member]
Pension plans, postretirement and other employee benefits [Line items]
Fair value of plan assets	19,954	24,713
Level 2 [Member]
Pension plans, postretirement and other employee benefits [Line items]
Fair value of plan assets	114,444	118,567
Level 3 [Member]
Pension plans, postretirement and other employee benefits [Line items]
Fair value of plan assets	29,878	29,714	¥ 43,343
Amount of unrealized profit (loss) of Level 3 assets	¥ (1,630)	4,853
Equities [Member]
Pension plans, postretirement and other employee benefits [Line items]
Plan assets of domestic plans investments	8.00%
Debt securities [Member]
Pension plans, postretirement and other employee benefits [Line items]
Plan assets of domestic plans investments	50.00%
Life insurance company general accounts [Member]
Pension plans, postretirement and other employee benefits [Line items]
Plan assets of domestic plans investments	28.00%
Life insurance company general accounts [Member] \| Level 1 [Member]
Pension plans, postretirement and other employee benefits [Line items]
Fair value of plan assets
Life insurance company general accounts [Member] \| Level 2 [Member]
Pension plans, postretirement and other employee benefits [Line items]
Fair value of plan assets	74,968	75,067
Life insurance company general accounts [Member] \| Level 3 [Member]
Pension plans, postretirement and other employee benefits [Line items]
Fair value of plan assets
Other investments [Member]
Pension plans, postretirement and other employee benefits [Line items]
Plan assets of domestic plans investments	14.00%
Other investments [Member] \| Level 1 [Member]
Pension plans, postretirement and other employee benefits [Line items]
Fair value of plan assets
Other investments [Member] \| Level 2 [Member]
Pension plans, postretirement and other employee benefits [Line items]
Fair value of plan assets	28,866	31,420
Other investments [Member] \| Level 3 [Member]
Pension plans, postretirement and other employee benefits [Line items]
Fair value of plan assets
Non-Japanese entities' plans [Member]
Pension plans, postretirement and other employee benefits [Line items]
Fair value of plan assets	24,148	24,121
Non-Japanese entities' plans [Member] \| Level 1 [Member]
Pension plans, postretirement and other employee benefits [Line items]
Fair value of plan assets	242	133
Non-Japanese entities' plans [Member] \| Level 2 [Member]
Pension plans, postretirement and other employee benefits [Line items]
Fair value of plan assets	3,098	3,102
Non-Japanese entities' plans [Member] \| Level 3 [Member]
Pension plans, postretirement and other employee benefits [Line items]
Fair value of plan assets	24,148	24,121
Amount of unrealized profit (loss) of Level 3 assets	(796)	(4,836)
Overseas Subsidiaries [Member]
Pension plans, postretirement and other employee benefits [Line items]
Recognized asset for pension benefits	¥ 726	¥ 5,798