Fair value of common stock issued by the Company included in plan assets.

No definition available.

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- Definition

This element represents the fair value of debt securities issued by the Company included in plan assets.

+ References

No definition available.

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- Definition

Percentage of fair value of common stock issued by the Company included in plan assets to the total fair value of plan assets.

+ References

No definition available.

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- Definition

This element represents the percentage fair value of debt securities issued by the Company to the total fair value of plan assets.

+ References

No definition available.

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- Definition

This element represents the eligible age of employee from when lifetime annuity payments commence.

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No definition available.

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- Definition

Number Of Major Fund Types

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No definition available.

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- Definition

Amount of cost of providing special or contractual termination benefits payable from defined benefit plan.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Severance Indemnities and Pension Plans (Narrative) (Detail) ¥ in Millions	12 Months Ended
	Mar. 31, 2026 JPY (¥) fund	Mar. 31, 2025 JPY (¥)	Mar. 31, 2024 JPY (¥)	Mar. 31, 2021
Defined Benefit Plan Disclosure [Line Items]
Eligible age for lifetime annuity payments				65 months
Special lump-sum early termination benefits charged to operations for the fiscal year	¥ 14,326	¥ 14,089	¥ 19,116
Pension benefits and SIPs
Defined Benefit Plan Disclosure [Line Items]
Number of major fund types \| fund	4
Domestic, Japan \| Pension benefits and SIPs \| Other debt securities and Japanese debt securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of debt securities issued by the MUFG Group included in plan assets	¥ 1,589	¥ 2,615
Percentage of fair value of debt securities issued by the MUFG Group to total fair value of plan assets	0.04%	0.07%
Domestic, Japan \| Pension benefits and SIPs \| Japanese marketable equity securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of common stock issued by the MUFG Group included in plan assets	¥ 7,353	¥ 7,076
Percentage of fair value of common stock issued by the MUFG Group to total fair value of plan assets	0.19%	0.20%