Accounting Policy [Line Items]

No definition available.

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- Definition

Amount of the effect of a change in accounting principle on Deferred tax assets.

+ References

No definition available.

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- Definition

New accounting pronouncement or change in accounting principle effect change on other liabilities.

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No definition available.

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- Definition

Amount of undisbursed portion of the loan receivable balance (loans in process). Excludes loans and leases covered under loss sharing agreements.

+ References

No definition available.

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- Definition

Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

+ References

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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- Definition

Amount of expense related to credit loss from transactions other than loan and lease transactions.

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- Definition

The cumulative amount of the reporting entity's undistributed earnings or deficit.

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Summary of accounting policies - Additional information (Detail) ¥ in Millions		6 Months Ended
	Apr. 01, 2020 JPY (¥)	Sep. 30, 2020 JPY (¥) Segment	Mar. 31, 2020 JPY (¥)
Accounting Policy [Line Items]
Number of business segments \| Segment		3
Retained earnings		¥ 1,775,691	¥ 1,645,451
Accounting Standards Update 2016-13 [Member]
Accounting Policy [Line Items]
New accounting standards impact on Other liabilities	¥ 638
New accounting standards impact on Deferred tax assets	72
Additional allowances for credit losses	1,972
Loans receivable	(9,774)
Loan commitment	5,888
Retained earnings	(15,662)
Accounting Standards Update 2016-13 [Member] \| Revision of Prior Period, Change in Accounting Principle, Adjustment [Member]
Accounting Policy [Line Items]
Retained earnings	¥ (2,538)