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Regulatory and Capital Adequacy - Capital Ratios Under Basel III (Details) $ in Millions | Dec. 31, 2024 USD ($) | Dec. 31, 2023 USD ($)
--- | --- | ---
Common equity Tier 1 capital: |  |
Capital Amount | $ 50,807 | $ 47,615
Capital Ratio | 0.135 | 0.129
Minimum Capital Adequacy | 0.045 | 0.045
Tier 1 capital |  |
Capital Amount | $ 55,652 | $ 52,460
Capital Ratio | 0.148 | 0.142
Minimum Capital Adequacy | 0.060 | 0.060
Well- Capitalized | 0.060 | 0.060
Total capital |  |
Capital Amount | $ 61,805 | $ 59,124
Capital Ratio | 0.164 | 0.160
Minimum Capital Adequacy | 0.080 | 0.080
Well- Capitalized | 0.100 | 0.100
Tier 1 leverage |  |
Capital Amount | $ 55,652 | $ 52,460
Capital Ratio | 0.116 | 0.112
Minimum Capital Adequacy | 0.040 | 0.040
Supplementary leverage |  |
Capital Amount | $ 55,652 | $ 52,460
Capital Ratio | 0.099 | 0.096
Minimum Capital Adequacy | 0.030 | 0.030
CONA: |  |
Common equity Tier 1 capital: |  |
Capital Amount | $ 51,118 | $ 47,933
Capital Ratio | 0.136 | 0.131
Minimum Capital Adequacy | 0.045 | 0.045
Well- Capitalized | 0.065 | 0.065
Tier 1 capital |  |
Capital Amount | $ 51,118 | $ 47,933
Capital Ratio | 0.136 | 0.131
Minimum Capital Adequacy | 0.060 | 0.060
Well- Capitalized | 0.080 | 0.080
Total capital |  |
Capital Amount | $ 56,937 | $ 52,636
Capital Ratio | 0.152 | 0.143
Minimum Capital Adequacy | 0.080 | 0.080
Well- Capitalized | 0.100 | 0.100
Tier 1 leverage |  |
Capital Amount | $ 51,118 | $ 47,933
Capital Ratio | 0.107 | 0.103
Minimum Capital Adequacy | 0.040 | 0.040
Well- Capitalized | 0.050 | 0.050
Supplementary leverage |  |
Capital Amount | $ 51,118 | $ 47,933
Capital Ratio | 0.092 | 0.088
Minimum Capital Adequacy | 0.030 | 0.030

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- Definition Tier One Common Capital Required To Be Well Capitalized To Risk Weighted Assets + References No definition available. + Details
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- Definition Amount of total capital as defined by regulatory framework. + 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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- Definition Ratio of minimum total risk-based capital to risk-weighted assets required for capital adequacy as defined by regulatory framework. + 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 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -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 + Details
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- Definition Amount of Common Equity Tier 1 risk-based capital as defined by regulatory framework. + 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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