Regulatory Requirements - Schedule of Regulatory Capital Amounts and Ratios (Details) $ in Millions	Jun. 30, 2026 USD ($)	Dec. 31, 2025 USD ($)
Happen, Inc. (Parent only)
Amount
CET1 capital	$ 1,436.2	$ 1,342.6
Tier 1 capital	1,436.2	1,342.6
Total capital	1,543.5	1,441.0
Tier 1 leverage	1,436.2	1,342.6
Risk-weighted assets	8,499.0	7,696.1
Quarterly adjusted average assets	$ 12,048.2	$ 11,174.0
Ratio
CET1 capital	0.169	0.174
Tier 1 capital	0.169	0.174
Total capital	0.182	0.187
Tier 1 leverage	0.119	0.120
Well-Capitalized Minimum
Tier 1 capital	0.060
Total capital	0.100
Happen Bank
Amount
CET1 capital	$ 1,315.7	$ 1,183.9
Tier 1 capital	1,315.7	1,183.9
Total capital	1,422.4	1,281.8
Tier 1 leverage	1,315.7	1,183.9
Risk-weighted assets	8,452.0	7,652.0
Quarterly adjusted average assets	$ 11,987.1	$ 11,090.4
Ratio
CET1 capital	0.156	0.155
Tier 1 capital	0.156	0.155
Total capital	0.168	0.168
Tier 1 leverage	0.110	0.107
Well-Capitalized Minimum
CET1 capital	0.065
Tier 1 capital	0.080
Total capital	0.100
Tier 1 leverage	0.050

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Actual Ratio

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Banking Regulation, Quarterly Adjusted Average Assets

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Ratio of minimum Common Equity Tier 1 risk-based capital to risk-weighted assets categorized as well capitalized as defined by regulatory framework for prompt corrective action.

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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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