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REGULATORY CAPITAL - Schedule of Basel III Requirements and the PCA well-capitalized Thresholds (Details) $ in Millions | Dec. 31, 2025 USD ($) | Dec. 31, 2024 USD ($)
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Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |  |
Basel III Requirements, Total risk-based capital | 0.1050 |
Basel III Requirements, Tier 1 risk-based capital | 0.0850 |
Basel III Requirements, Common equity Tier 1 | 0.0700 |
Basel III Requirements, Tier 1 leverage | 0.0400 |
PCA well-capitalized thresholds, Total risk-based capital | 0.1000 |
PCA well-capitalized thresholds, Tier 1 risk-based capital | 0.0800 |
PCA well-capitalized thresholds, Common equity Tier 1 | 0.0650 |
PCA well-capitalized thresholds, Tier 1 leverage | 0.0500 |
Total risk-based capital, amount | $ 24,945 | $ 24,610
Tier 1 risk-based capital, amount | 21,660 | 22,137
Common equity Tier 1, amount | 20,285 | 21,256
Tier 1 leverage, amount | $ 21,660 | $ 22,137
Total risk-based capital, Ratio | 0.1371 | 0.1504
Tier 1 risk-based capital, Ratio | 0.1191 | 0.1353
Common equity Tier 1, Ratio | 0.1115 | 0.1299
Tier 1 leverage, Ratio | 0.0929 | 0.0990
FCB |  |
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |  |
Basel III Requirements, Total risk-based capital | 0.1050 |
Basel III Requirements, Tier 1 risk-based capital | 0.0850 |
Basel III Requirements, Common equity Tier 1 | 0.0700 |
Basel III Requirements, Tier 1 leverage | 0.0400 |
PCA well-capitalized thresholds, Total risk-based capital | 0.1000 |
PCA well-capitalized thresholds, Tier 1 risk-based capital | 0.0800 |
PCA well-capitalized thresholds, Common equity Tier 1 | 0.0650 |
PCA well-capitalized thresholds, Tier 1 leverage | 0.0500 |
Total risk-based capital, amount | $ 24,739 | $ 23,975
Tier 1 risk-based capital, amount | 22,796 | 21,852
Common equity Tier 1, amount | 22,796 | 21,852
Tier 1 leverage, amount | $ 22,796 | $ 21,852
Total risk-based capital, Ratio | 0.1362 | 0.1466
Tier 1 risk-based capital, Ratio | 0.1255 | 0.1337
Common equity Tier 1, Ratio | 0.1255 | 0.1337
Tier 1 leverage, Ratio | 0.0979 | 0.0978

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- Definition 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. + 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 + Details
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