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Regulatory Capital (Details) - USD ($) $ in Thousands | Oct. 12, 2018 | Mar. 31, 2019 | Dec. 31, 2018
--- | --- | --- | ---
Total Capital (to Risk Weighted Assets), Amount |  |  |
Actual, Amount |  | $ 1,009,053 | $ 894,572
Minimum Capital Requirement, Amount |  | 578,555 | 482,638
Minimum To Be Well Capitalized, Amount |  | $ 723,194 | $ 603,297
Total Capital (to Risk Weighted Assets), Ratio |  |  |
Actual, Ratio (as a percent) |  | 13.95% | 14.83%
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 |  | $ 898,138 | $ 783,924
Minimum Capital Requirement, Amount |  | 433,917 | 361,978
Minimum To Be Well Capitalized, Amount |  | $ 578,555 | $ 482,638
Tier 1 Capital (to Risk Weighted Assets), Ratio |  |  |
Actual, Ratio (as a percent) |  | 12.42% | 12.99%
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 |  | $ 824,138 | $ 709,924
Minimum Capital Requirement, Amount |  | 325,438 | 271,484
Minimum To Be Well Capitalized, Amount |  | $ 470,076 | $ 392,143
Common Equity Tier 1 Capital (to Risk Weighted Assets), Ratio |  |  |
Actual, Ratio (as a percent) |  | 11.40% | 11.77%
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 |  | $ 898,138 | $ 783,924
Minimum Capital Requirement, Amount |  | $ 340,417 | $ 302,704
Tier 1 Capital (to Average Assets), Ratio |  |  |
Actual, Ratio (as a percent) |  | 10.55% | 10.36%
Minimum Capital Requirement, Ratio (as a percent) |  | 4.00% | 4.00%
Busey Bank |  |  |
Total Capital (to Risk Weighted Assets), Amount |  |  |
Actual, Amount |  | $ 882,181 | $ 854,351
Minimum Capital Requirement, Amount |  | 487,119 | 481,701
Minimum To Be Well Capitalized, Amount |  | $ 608,899 | $ 602,126
Total Capital (to Risk Weighted Assets), Ratio |  |  |
Actual, Ratio (as a percent) |  | 14.49% | 14.19%
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 |  | $ 831,371 | $ 803,703
Minimum Capital Requirement, Amount |  | 365,340 | 361,276
Minimum To Be Well Capitalized, Amount |  | $ 487,119 | $ 481,701
Tier 1 Capital (to Risk Weighted Assets), Ratio |  |  |
Actual, Ratio (as a percent) |  | 13.65% | 13.35%
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 |  | $ 831,371 | $ 803,703
Minimum Capital Requirement, Amount |  | 274,005 | 270,957
Minimum To Be Well Capitalized, Amount |  | $ 395,785 | $ 391,382
Common Equity Tier 1 Capital (to Risk Weighted Assets), Ratio |  |  |
Actual, Ratio (as a percent) |  | 13.65% | 13.35%
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 |  | $ 831,371 | $ 803,703
Minimum Capital Requirement, Amount |  | 295,723 | 302,232
Minimum To Be Well Capitalized, Amount |  | $ 369,654 | $ 377,789
Tier 1 Capital (to Average Assets), Ratio |  |  |
Actual, Ratio (as a percent) |  | 11.25% | 10.64%
Minimum Capital Requirement, Ratio (as a percent) |  | 4.00% | 4.00%
Minimum To Be Well Capitalized, Ratio (as a percent) |  | 5.00% | 5.00%
Banc Ed |  |  |
Total Capital (to Risk Weighted Assets), Amount |  |  |
Actual, Amount |  | $ 190,105 |
Minimum Capital Requirement, Amount |  | 90,646 |
Minimum To Be Well Capitalized, Amount |  | $ 113,308 |
Total Capital (to Risk Weighted Assets), Ratio |  |  |
Actual, Ratio (as a percent) |  | 16.78% |
Minimum Capital Requirement, Ratio (as a percent) |  | 8.00% |
Minimum To Be Well Capitalized, Ratio (as a percent) |  | 10.00% |
Tier 1 Capital (to Risk Weighted Assets), Amount |  |  |
Actual, Amount |  | $ 190,000 |
Minimum Capital Requirement, Amount |  | 67,985 |
Minimum To Be Well Capitalized, Amount |  | $ 90,646 |
Tier 1 Capital (to Risk Weighted Assets), Ratio |  |  |
Actual, Ratio (as a percent) |  | 16.77% |
Minimum Capital Requirement, Ratio (as a percent) |  | 6.00% |
Minimum To Be Well Capitalized, Ratio (as a percent) |  | 8.00% |
Common Equity Tier 1 Capital (to Risk Weighted Assets), Amount |  |  |
Actual, Amount |  | $ 190,000 |
Minimum Capital Requirement, Amount |  | 50,989 |
Minimum To Be Well Capitalized, Amount |  | $ 73,650 |
Common Equity Tier 1 Capital (to Risk Weighted Assets), Ratio |  |  |
Actual, Ratio (as a percent) |  | 16.77% |
Minimum Capital Requirement, Ratio (as a percent) |  | 4.50% |
Minimum To Be Well Capitalized, Ratio (as a percent) |  | 6.50% |
Tier 1 Capital (to Average Assets), Amount |  |  |
Actual, Amount |  | $ 190,000 |
Minimum Capital Requirement, Amount |  | 68,472 |
Minimum To Be Well Capitalized, Amount |  | $ 85,589 |
Tier 1 Capital (to Average Assets), Ratio |  |  |
Actual, Ratio (as a percent) |  | 11.10% |
Minimum Capital Requirement, Ratio (as a percent) |  | 4.00% |
Minimum To Be Well Capitalized, Ratio (as a percent) |  | 5.00% |
Busey Bank |  |  |
Regulatory Capital |  |  |
Distribution received through chartered amendment | $ 40,000 |  |

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- Definition The amount of Total Capital required to be categorized as well as capitalized under the regulatory framework for prompt corrective action. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958568-112826 + Details
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- Definition The minimum amount of Tier 1 Leverage Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=84167132&loc=d3e65071-112826 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958568-112826 + Details
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- Definition The minimum amount of Tier 1 Leverage Capital for capital adequacy purposes divided by average assets as defined in the regulations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958568-112826 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=84167132&loc=d3e65071-112826 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958570-112826 + Details
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- Definition The amount of Tier 1 Leverage Capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958568-112826 + Details
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- Definition The minimum Tier One Capital Ratio (Tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958568-112826 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958570-112826 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=84167132&loc=d3e65071-112826 + Details
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- Definition The amount of Tier 1 Risk Based Capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958568-112826 + Details
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- Definition The Tier 1 capital ratio (Tier 1 capital divided by risk weighted assets) required to be categorized as "well capitalized" under the regulatory framework for prompt corrective action. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958568-112826 + Details
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