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Minimum Regulatory Capital Requirements - Additional Information (Detail) | Dec. 31, 2024 | Dec. 31, 2023 | Jan. 01, 2019
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Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items] |  |  |
Minimum ratio of capital to risk-weighted assets | 0.08 | 0.08 | 0.080
Minimum ratio of capital to risk-weighted assets including capital conservation buffer |  |  | 10.50%
Minimum leverage ratio calculated as ratio of Tier 1 capital to average quarterly assets | 0.0812 | 0.0786 | 0.040
Common Equity Tier 1 Capital [Member] |  |  |
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items] |  |  |
Minimum ratio of capital to risk-weighted assets |  |  | 0.045
Capital conservation buffer |  |  | 2.50%
Minimum ratio of capital to risk-weighted assets including capital conservation buffer |  |  | 7.00%
Tier 1 Capital [Member] |  |  |
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items] |  |  |
Minimum ratio of capital to risk-weighted assets |  |  | 0.060
Minimum ratio of capital to risk-weighted assets including capital conservation buffer |  |  | 8.50%

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- Definition Capital required for capital adequacy to risk weighted assets including capital conservation buffer. + References No definition available. + Details
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- Definition Risk weighted assets capital conservation buffer. + References No definition available. + Details
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- Definition Ratio of minimum total risk-based capital to risk-weighted assets required for capital adequacy as defined by regulatory framework. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 942 -SubTopic 505 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (c)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477270/942-505-50-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 942 -SubTopic 505 -Name Accounting Standards Codification -Section 50 -Paragraph 1B -Publisher FASB -URI https://asc.fasb.org/1943274/2147477270/942-505-50-1B + Details
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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 Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 942 -SubTopic 505 -Name Accounting Standards Codification -Section 50 -Paragraph 1B -Publisher FASB -URI https://asc.fasb.org/1943274/2147477270/942-505-50-1B Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 942 -SubTopic 505 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (c)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477270/942-505-50-1 + Details
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