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Regulatory Capital - Schedule of Basel III Requirements and the PCA well-capitalized Thresholds (Details) $ in Millions | Sep. 30, 2023 USD ($) | Dec. 31, 2022 USD ($)
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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 | $ 23,351 | $ 11,799
Tier 1 risk-based capital, amount | 20,643 | 9,902
Common equity Tier 1, amount | 19,762 | 9,021
Tier 1 leverage, amount | $ 20,643 | $ 9,902
Total risk-based capital, Ratio | 0.1564 | 0.1318
Tier 1 risk-based capital, Ratio | 0.1383 | 0.1106
Common equity Tier 1, Ratio | 0.1324 | 0.1008
Tier 1 leverage, Ratio | 0.0973 | 0.0899
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 | $ 22,927 | $ 11,627
Tier 1 risk-based capital, amount | 20,673 | 10,186
Common equity Tier 1, amount | 20,673 | 10,186
Tier 1 leverage, amount | $ 20,673 | $ 10,186
Total risk-based capital, Ratio | 0.1536 | 0.1299
Tier 1 risk-based capital, Ratio | 0.1385 | 0.1138
Common equity Tier 1, Ratio | 0.1385 | 0.1138
Tier 1 leverage, Ratio | 0.0975 | 0.0925

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- Definition Banking Regulation, Tier One Leverage Capital Ratio, Capital Adequacy Including Conservation Buffer, Minimum + References No definition available. + Details
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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//1943274/2147480696/942-505-50-1 + Details
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