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Regulatory Capital (Details) - USD ($) $ in Thousands |  | 3 Months Ended |
--- | --- | --- | ---
Jun. 01, 2020 | Jun. 30, 2020 | Dec. 31, 2019
Total Capital (to Risk Weighted Assets), Amount |  |  |
Actual, Amount |  | $ 1,200,278 | $ 1,036,143
Minimum Capital Requirement, Amount |  | 591,499 | 590,826
Minimum To Be Well Capitalized, Amount |  | $ 739,374 | $ 738,532
Total Capital (to Risk Weighted Assets), Ratio |  |  |
Actual, Ratio (as a percent) |  | 16.23% | 14.03%
Minimum Capital Requirement, Ratio (as a percent) |  | 8.00% | 8.00%
Minimum To Be Well Capitalized, Ratio (as a percent) |  | 10.00% | 10.00%
Tier 1 Capital (to Risk Weighted Assets), Amount |  |  |
Actual, Amount |  | $ 941,243 | $ 922,395
Minimum Capital Requirement, Amount |  | 443,624 | 443,120
Minimum To Be Well Capitalized, Amount |  | $ 591,499 | $ 590,826
Tier 1 Capital (to Risk Weighted Assets), Ratio |  |  |
Actual, Ratio (as a percent) |  | 12.73% | 12.49%
Minimum Capital Requirement, Ratio (as a percent) |  | 6.00% | 6.00%
Minimum To Be Well Capitalized, Ratio (as a percent) |  | 8.00% | 8.00%
Common Equity Tier 1 Capital (to Risk Weighted Assets), Amount |  |  |
Actual, Amount |  | $ 867,243 | $ 848,395
Minimum Capital Requirement, Amount |  | 332,718 | 332,340
Minimum To Be Well Capitalized, Amount |  | $ 480,593 | $ 480,046
Common Equity Tier 1 Capital (to Risk Weighted Assets), Ratio |  |  |
Actual, Ratio (as a percent) |  | 11.73% | 11.49%
Minimum Capital Requirement, Ratio (as a percent) |  | 4.50% | 4.50%
Minimum To Be Well Capitalized, Ratio (as a percent) |  | 6.50% | 6.50%
Tier 1 Capital (to Average Assets), Amount |  |  |
Actual, Amount |  | $ 941,243 | $ 922,395
Minimum Capital Requirement, Amount |  | $ 399,631 | $ 373,360
Tier 1 Capital (to Average Assets), Ratio |  |  |
Actual, Ratio (as a percent) |  | 9.42% | 9.88%
Minimum Capital Requirement, Ratio (as a percent) |  | 4.00% | 4.00%
Busey Bank |  |  |
Total Capital (to Risk Weighted Assets), Amount |  |  |
Actual, Amount |  | $ 1,056,068 | $ 1,099,449
Minimum Capital Requirement, Amount |  | 590,746 | 589,681
Minimum To Be Well Capitalized, Amount |  | $ 738,433 | $ 737,101
Total Capital (to Risk Weighted Assets), Ratio |  |  |
Actual, Ratio (as a percent) |  | 14.30% | 14.92%
Minimum Capital Requirement, Ratio (as a percent) |  | 8.00% | 8.00%
Minimum To Be Well Capitalized, Ratio (as a percent) |  | 10.00% | 10.00%
Tier 1 Capital (to Risk Weighted Assets), Amount |  |  |
Actual, Amount |  | $ 982,033 | $ 1,045,701
Minimum Capital Requirement, Amount |  | 443,060 | 442,261
Minimum To Be Well Capitalized, Amount |  | $ 590,746 | $ 589,681
Tier 1 Capital (to Risk Weighted Assets), Ratio |  |  |
Actual, Ratio (as a percent) |  | 13.30% | 14.19%
Minimum Capital Requirement, Ratio (as a percent) |  | 6.00% | 6.00%
Minimum To Be Well Capitalized, Ratio (as a percent) |  | 8.00% | 8.00%
Common Equity Tier 1 Capital (to Risk Weighted Assets), Amount |  |  |
Actual, Amount |  | $ 982,033 | $ 1,045,701
Minimum Capital Requirement, Amount |  | 332,295 | 331,696
Minimum To Be Well Capitalized, Amount |  | $ 479,981 | $ 479,116
Common Equity Tier 1 Capital (to Risk Weighted Assets), Ratio |  |  |
Actual, Ratio (as a percent) |  | 13.30% | 14.19%
Minimum Capital Requirement, Ratio (as a percent) |  | 4.50% | 4.50%
Minimum To Be Well Capitalized, Ratio (as a percent) |  | 6.50% | 6.50%
Tier 1 Capital (to Average Assets), Amount |  |  |
Actual, Amount |  | $ 982,033 | $ 1,045,701
Minimum Capital Requirement, Amount |  | 399,926 | 373,639
Minimum To Be Well Capitalized, Amount |  | $ 499,907 | $ 467,049
Tier 1 Capital (to Average Assets), Ratio |  |  |
Actual, Ratio (as a percent) |  | 9.82% | 11.19%
Minimum Capital Requirement, Ratio (as a percent) |  | 4.00% | 4.00%
Minimum To Be Well Capitalized, Ratio (as a percent) |  | 5.00% | 5.00%
Subordinated debt | 5.25% fixed-to-floating rate notes due 2030 |  |  |
Regulatory Capital |  |  |
Proceeds from public offering | $ 125,000 | $ 125,000 |

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