Ratio of total risk-based capital to risk-weighted assets as defined by regulatory framework.

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

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Ratio of Common Equity Tier 1 risk-based capital to risk-weighted assets as defined by regulatory framework.

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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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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
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-SubTopic 505
-Name Accounting Standards Codification
-Section 50
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-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477270/942-505-50-1

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

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Ratio of Tier 1 risk-based capital to risk-weighted assets as defined by regulatory framework.

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Regulatory and Operational Matters - Narrative (Details) - Subsidiaries	Sep. 30, 2025	Jan. 17, 2025	Dec. 31, 2024	Apr. 17, 2024
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Common equity tier 1 capital ratio, actual	0.1854		0.0758
Tier 1 capital ratio, actual	0.1854		0.0758
Tier 1 leverage capital ratio, actual	0.1195		0.0579
Total risk-based capital ratio, actual	0.1919		0.0771
Mandated Ratio
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Common equity tier 1 capital ratio, actual		0.1000		0.1000
Tier 1 capital ratio, actual		0.1000		0.1000
Tier 1 leverage capital ratio, actual		0.0900		0.0900
Total risk-based capital ratio, actual		0.1150		0.1150