Goodwill and Other Intangible Assets (Other Intangible Assets) (Detail) - JPY (¥) ¥ in Millions	Mar. 31, 2024	Mar. 31, 2023
Indefinite-lived intangible assets:
Trademarks and trade names	¥ 126,192	¥ 115,049
Asset management contracts	57,928	51,558
Others	3,156	12,375
Indefinite-Lived Intangible Assets (Excluding Goodwill), Total	187,276	178,982
Intangible assets subject to amortization:
Software	142,049	141,747
Customer relationships	184,475	161,936
Asset management contracts	117,043	104,481
Others	165,130	154,413
Finite-Lived Intangible Assets, Gross, Total	608,697	562,577
Accumulated amortization	(263,023)	(223,417)
Net	345,674	339,160
Intangible Assets, Net (Excluding Goodwill), Total	¥ 532,950	¥ 518,142

Amount before accumulated amortization of capitalized costs for computer software, including but not limited to, acquired and internally developed computer software.

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Gross carrying amount before accumulated amortization as of the balance sheet date of an intangible asset that arises from a contractual arrangement with a third party (not including franchise rights and license agreements).

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Gross carrying amount before accumulated amortization as of the balance sheet date to an asset acquired in a business combination representing a favorable existing relationship with customers having a finite beneficial life.

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Carrying amount (original costs adjusted for previously recognized amortization and impairment) as of the balance sheet date of rights with an indefinite period of benefit that arose from a contractual arrangement with a third party (not including franchise rights and license agreements).

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Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.

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Carrying amount (original costs adjusted for previously recognized amortization and impairment) as of the balance sheet date for the rights acquired through registration of a trade name to gain or protect exclusive use thereof for a projected indefinite period of benefit.

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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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Amount before accumulated amortization of finite-lived intangible assets classified as other.

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Amount after impairment of indefinite-lived intangible assets classified as other. Excludes financial assets and goodwill.

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