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Regulatory Capital - Additional Information (Detail) $ in Billions	9 Months Ended
	Mar. 31, 2023 USD ($)	Mar. 31, 2020
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Capital conservation buffer risk-weighted assets	2.50%
Maximum asset value required to be maintained leverage ratio	$ 10
Maximum [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Leverage ratio		0.09

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- Definition

Maximum Asset Value Required To Be Maintained Leverage Ratio.

+ References

No definition available.

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- Definition

Tier one risk based capital to risk weighted assets conservation buffer.

+ References

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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.

+ References

No definition available.

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- Definition

Ratio of Tier 1 capital to average assets as defined by regulatory framework.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-URI https://asc.fasb.org/extlink&oid=117337116&loc=SL5958568-112826

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