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REGULATORY CAPITAL - Schedule of Basel III Requirements and the PCA well-capitalized Thresholds (Details) $ in Millions | Dec. 31, 2024 USD ($) | Dec. 31, 2023 USD ($)
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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 | $ 24,610 | $ 23,891
Tier 1 risk-based capital, amount | 22,137 | 21,150
Common equity Tier 1, amount | 21,256 | 20,270
Tier 1 leverage, amount | $ 22,137 | $ 21,150
Total risk-based capital, Ratio | 0.1504 | 0.1575
Tier 1 risk-based capital, Ratio | 0.1353 | 0.1394
Common equity Tier 1, Ratio | 0.1299 | 0.1336
Tier 1 leverage, Ratio | 0.0990 | 0.0983
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 | $ 23,975 | $ 23,600
Tier 1 risk-based capital, amount | 21,852 | 21,227
Common equity Tier 1, amount | 21,852 | 21,227
Tier 1 leverage, amount | $ 21,852 | $ 21,227
Total risk-based capital, Ratio | 0.1466 | 0.1556
Tier 1 risk-based capital, Ratio | 0.1337 | 0.1399
Common equity Tier 1, Ratio | 0.1337 | 0.1399
Tier 1 leverage, Ratio | 0.0978 | 0.0988

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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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