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Regulatory Requirements and Matters (Regulatory Capital Information (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018
Well Capitalized Requirement |  |
Fully phased-in capital conservation buffer | 2.50% |
Transition capital conservation buffer, percent |  | 1.875%
Company |  |
Actual |  |
Total capital (to risk-weighted assets), Amount | $ 5,064,037 | $ 4,438,730
Tier I capital (to risk-weighted assets), Amount | 4,546,592 | 3,966,842
Tier 1 Common Equity capital (to risk-weighted assets), Amount | 4,546,592 | 3,966,842
Tier 1 leverage capital (to adjusted average assets), Amount | 4,546,592 | 3,966,842
Risk-weighted assets | 35,136,427 | 32,497,296
Adjusted quarterly average total assets | $ 44,449,802 | $ 40,636,402
Total capital (to risk-weighted assets), Ratio (as a percent) | 14.40% | 13.70%
Tier I capital (to risk-weighted assets), Ratio (as a percent) | 12.90% | 12.20%
Tier 1 Common Equity capital (to risk-weighted assets), Ratio (as a percent) | 12.90% | 12.20%
Tier 1 leverage capital (to adjusted average assets), Ratio (as a percent) | 10.30% | 9.90%
Minimum Capital Ratios |  |
Total capital (to risk-weighted assets), Ratio (as a percent) | 10.50% | 9.88%
Tier I capital (to risk-weighted assets), Ratio (as a percent) | 8.50% | 7.88%
Tier 1 Common Equity Capital (to risk-weighted assets), Ratio (as a percent) | 7.00% | 6.38%
Tier 1 leverage capital (to adjusted average assets), Ratio (as a percent) | 4.00% | 4.00%
Well Capitalized Requirement |  |
Total capital (to risk-weighted assets), Ratio (as a percent) | 10.00% | 10.00%
Tier I capital (to risk-weighted assets), Ratio (as a percent) | 8.00% | 8.00%
Tier 1 Common Equity capital (to risk-weighted assets), Ratio (as a percent) | 6.50% | 6.50%
East West Bank |  |
Actual |  |
Total capital (to risk-weighted assets), Amount | $ 4,886,237 | $ 4,268,616
Tier I capital (to risk-weighted assets), Amount | 4,516,792 | 3,944,728
Tier 1 Common Equity capital (to risk-weighted assets), Amount | 4,516,792 | 3,944,728
Tier 1 leverage capital (to adjusted average assets), Amount | 4,516,792 | 3,944,728
Risk-weighted assets | 35,127,920 | 32,477,002
Adjusted quarterly average total assets | $ 44,419,308 | $ 40,611,215
Total capital (to risk-weighted assets), Ratio (as a percent) | 13.90% | 13.10%
Tier I capital (to risk-weighted assets), Ratio (as a percent) | 12.90% | 12.10%
Tier 1 Common Equity capital (to risk-weighted assets), Ratio (as a percent) | 12.90% | 12.10%
Tier 1 leverage capital (to adjusted average assets), Ratio (as a percent) | 10.30% | 9.80%
Minimum Capital Ratios |  |
Total capital (to risk-weighted assets), Ratio (as a percent) | 10.50% | 9.88%
Tier I capital (to risk-weighted assets), Ratio (as a percent) | 8.50% | 7.88%
Tier 1 Common Equity Capital (to risk-weighted assets), Ratio (as a percent) | 7.00% | 6.38%
Tier 1 leverage capital (to adjusted average assets), Ratio (as a percent) | 4.00% | 4.00%
Well Capitalized Requirement |  |
Total capital (to risk-weighted assets), Ratio (as a percent) | 10.00% | 10.00%
Tier I capital (to risk-weighted assets), Ratio (as a percent) | 8.00% | 8.00%
Tier 1 Common Equity capital (to risk-weighted assets), Ratio (as a percent) | 6.50% | 6.50%
Tier 1 leverage capital (to adjusted average assets), Ratio (as a percent) | 5.00% | 5.00%

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