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Regulatory and Capital Adequacy - Capital Ratios Under Basel III (Details) $ in Millions | Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($)
--- | --- | ---
Common equity Tier 1 capital: |  |
Capital Amount | $ 47,615 | $ 44,731
Capital Ratio | 0.129 | 0.125
Minimum Capital Adequacy | 0.045 | 0.045
Tier 1 capital |  |
Capital Amount | $ 52,460 | $ 49,576
Capital Ratio | 0.142 | 0.139
Minimum Capital Adequacy | 0.060 | 0.060
Well- Capitalized | 0.060 | 0.060
Total capital |  |
Capital Amount | $ 59,124 | $ 56,714
Capital Ratio | 0.160 | 0.158
Minimum Capital Adequacy | 0.080 | 0.080
Well- Capitalized | 0.100 | 0.100
Tier 1 leverage |  |
Capital Amount | $ 52,460 | $ 49,576
Capital Ratio | 0.112 | 0.111
Minimum Capital Adequacy | 0.040 | 0.040
Supplementary leverage |  |
Capital Amount | $ 52,460 | $ 49,576
Capital Ratio | 0.096 | 0.095
Minimum Capital Adequacy | 0.030 | 0.030
CONA: |  |
Common equity Tier 1 capital: |  |
Capital Amount | $ 47,933 | $ 46,630
Capital Ratio | 0.131 | 0.131
Minimum Capital Adequacy | 0.045 | 0.045
Well- Capitalized | 0.065 | 0.065
Tier 1 capital |  |
Capital Amount | $ 47,933 | $ 46,630
Capital Ratio | 0.131 | 0.131
Minimum Capital Adequacy | 0.060 | 0.060
Well- Capitalized | 0.080 | 0.080
Total capital |  |
Capital Amount | $ 52,636 | $ 51,165
Capital Ratio | 0.143 | 0.144
Minimum Capital Adequacy | 0.080 | 0.080
Well- Capitalized | 0.100 | 0.100
Tier 1 leverage |  |
Capital Amount | $ 47,933 | $ 46,630
Capital Ratio | 0.103 | 0.105
Minimum Capital Adequacy | 0.040 | 0.040
Well- Capitalized | 0.050 | 0.050
Supplementary leverage |  |
Capital Amount | $ 47,933 | $ 46,630
Capital Ratio | 0.088 | 0.090
Minimum Capital Adequacy | 0.030 | 0.030

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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//1943274/2147480696/942-505-50-1 + 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//1943274/2147480696/942-505-50-1 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//1943274/2147480696/942-505-50-1B + 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//1943274/2147480696/942-505-50-1 + Details
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