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Regulatory Requirements and Matters - Regulatory Capital Information (Details) $ in Thousands | 12 Months Ended
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Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($)
Minimum Capital Ratios |  |
Total capital ratio required for capital adequacy to risk weighted assets | 0.080 |
Tier 1 risk based capital ratio required for capital adequacy to risk weighted assets | 0.060 |
Common equity tier 1 capital adequacy to risk weighted assets | 0.045 |
Tier 1 leverage capital (to adjusted average assets), Ratio (as a percent) | 0.040 |
Well-Capitalized Requirement |  |
Fully phased-in capital conservation buffer | 2.50% |
Company |  |
Actual |  |
Total capital (to risk-weighted assets), Amount | $ 7,919,407 | $ 7,003,299
Tier I capital (to risk-weighted assets), Amount | 7,140,778 | 6,347,108
Tier 1 Common Equity capital (to risk-weighted assets), Amount | 7,140,778 | 6,347,108
Tier 1 leverage capital (to adjusted average assets), Amount | 7,140,778 | 6,347,108
Risk-weighted assets | 53,663,392 | 50,036,719
Adjusted quarterly average total assets | $ 70,406,008 | $ 65,221,597
Total capital (to risk-weighted assets), Ratio (as a percent) | 0.148 | 0.140
Tier I capital (to risk-weighted assets), Ratio (as a percent) | 0.133 | 0.127
Tier 1 Common Equity capital (to risk-weighted assets), Ratio (as a percent) | 0.133 | 0.127
Tier 1 leverage capital (to adjusted average assets), Ratio (as a percent) | 0.102 | 0.098
Minimum Capital Ratios |  |
Total capital ratio required for capital adequacy to risk weighted assets | 0.080 |
Tier 1 risk based capital ratio required for capital adequacy to risk weighted assets | 0.060 |
Common equity tier 1 capital adequacy to risk weighted assets | 0.045 |
Tier 1 leverage capital (to adjusted average assets), Ratio (as a percent) | 0.040 |
Fully phased-in minimum capital ratios |  |
Total capital (to risk-weighted assets), Ratio (as a percent) | 10.50% |
Tier I capital (to risk-weighted assets), Ratio (as a percent) | 8.50% |
Tier 1 Common Equity Capital (to risk-weighted assets), Ratio (as a percent) | 7.00% |
Tier 1 leverage capital (to adjusted average assets), Ratio (as a percent) | 4.00% |
Well-Capitalized Requirement |  |
Total capital (to risk-weighted assets), Ratio (as a percent) | 0.100 |
Tier I capital (to risk-weighted assets), Ratio (as a percent) | 0.060 |
East West Bank |  |
Actual |  |
Total capital (to risk-weighted assets), Amount | $ 7,363,575 | $ 6,760,612
Tier I capital (to risk-weighted assets), Amount | 6,732,946 | 6,252,421
Tier 1 Common Equity capital (to risk-weighted assets), Amount | 6,732,946 | 6,252,421
Tier 1 leverage capital (to adjusted average assets), Amount | 6,732,946 | 6,252,421
Risk-weighted assets | 53,539,980 | 50,024,772
Adjusted quarterly average total assets | $ 70,270,449 | $ 65,198,267
Total capital (to risk-weighted assets), Ratio (as a percent) | 0.138 | 0.135
Tier I capital (to risk-weighted assets), Ratio (as a percent) | 0.126 | 0.125
Tier 1 Common Equity capital (to risk-weighted assets), Ratio (as a percent) | 0.126 | 0.125
Tier 1 leverage capital (to adjusted average assets), Ratio (as a percent) | 0.096 | 0.097
Minimum Capital Ratios |  |
Total capital ratio required for capital adequacy to risk weighted assets | 0.080 |
Tier 1 risk based capital ratio required for capital adequacy to risk weighted assets | 0.060 |
Common equity tier 1 capital adequacy to risk weighted assets | 0.045 |
Tier 1 leverage capital (to adjusted average assets), Ratio (as a percent) | 0.040 |
Fully phased-in minimum capital ratios |  |
Total capital (to risk-weighted assets), Ratio (as a percent) | 10.50% |
Tier I capital (to risk-weighted assets), Ratio (as a percent) | 8.50% |
Tier 1 Common Equity Capital (to risk-weighted assets), Ratio (as a percent) | 7.00% |
Tier 1 leverage capital (to adjusted average assets), Ratio (as a percent) | 4.00% |
Well-Capitalized Requirement |  |
Total capital (to risk-weighted assets), Ratio (as a percent) | 0.100 |
Tier I capital (to risk-weighted assets), Ratio (as a percent) | 0.080 |
Tier 1 Common Equity Capital (to risk-weighted assets), Ratio (as a percent) | 0.065 |
Tier 1 leverage capital (to adjusted average assets), Ratio (as a percent) | 0.050 |

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