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Regulatory Capital (Regulatory Capital Ratios) (Details) - USD ($) $ in Thousands | Mar. 31, 2020 | Dec. 31, 2019
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Compliance with Regulatory Capital Requirements under Banking Regulations |  |
Total capital | $ 242,869 | $ 239,029
Total capital to risk-weighted assets | 11.74% | 12.01%
Total capital, Minimum Required for Capital Adequacy Purposes | $ 165,436 | $ 159,185
Total capital to risk-weighted assets, Minimum Required for Capital Adequacy Purposes | 8.00% | 8.00%
Capital Required for Capital Adequacy Plus Capital Conservation Buffer | $ 217,135 | $ 208,930
Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets | 10.50% | 10.50%
Tier 1 capital | $ 195,318 | $ 194,456
Tier 1 capital to risk-weighted assets | 9.45% | 9.77%
Tier 1 capital, Minimum Required for Capital Adequacy Purposes | $ 124,077 | $ 119,388
Tier 1 capital to risk-weighted assets, Minimum Required for Capital Adequacy Purposes | 6.00% | 6.00%
Tier One Risk Based Capital Required for Capital Adequacy Plus Capital Conservation Buffer | $ 175,776 | $ 169,134
Tier One Risk Based Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets | 8.50% | 8.50%
Common equity tier 1 capital | $ 185,267 | $ 184,409
Common equity tier 1 capital to risk-weighted assets | 8.96% | 9.27%
Common equity tier 1 capital, Minimum Required for Capital Adequacy Purposes | $ 93,058 | $ 89,541
Common equity tier 1 capital to risk-weighted assets, Minimum Required for Capital Adequacy Purposes | 4.50% | 4.50%
Common Equity Tier One Capital Required for Capital Adequacy Plus Capital Conservation Buffer | $ 144,756 | $ 139,286
Common Equity Tier One Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets | 7.00% | 7.00%
Tier 1 leverage capital | $ 195,318 | $ 194,456
Tier 1 leverage capital to average assets | 9.33% | 9.27%
Tier 1 leverage capital, Minimum Required for Capital Adequacy Purposes | $ 83,754 | $ 83,950
Tier 1 leverage capital to average assets, Minimum Required for Capital Adequacy Purposes | 4.00% | 4.00%
Tier One Leverage Capital Required for Capital Adequacy Plus Capital Conservation Buffer | $ 83,754 | $ 83,950
Tier One Leverage Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets | 4.00% | 4.00%
First Business Bank |  |
Compliance with Regulatory Capital Requirements under Banking Regulations |  |
Total capital | $ 234,506 | $ 233,181
Total capital to risk-weighted assets | 11.41% | 11.79%
Total capital, Minimum Required for Capital Adequacy Purposes | $ 164,397 | $ 158,177
Total capital to risk-weighted assets, Minimum Required for Capital Adequacy Purposes | 8.00% | 8.00%
Capital Required for Capital Adequacy Plus Capital Conservation Buffer | $ 215,771 | $ 207,607
Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets | 10.50% | 10.50%
Total capital, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | $ 205,496 | $ 197,721
Total capital to risk-weighted assets, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | 10.00% | 10.00%
Tier 1 capital | $ 210,672 | $ 212,315
Tier 1 capital to risk-weighted assets | 10.25% | 10.74%
Tier 1 capital, Minimum Required for Capital Adequacy Purposes | $ 123,298 | $ 118,633
Tier 1 capital to risk-weighted assets, Minimum Required for Capital Adequacy Purposes | 6.00% | 6.00%
Tier One Risk Based Capital Required for Capital Adequacy Plus Capital Conservation Buffer | $ 174,672 | $ 168,063
Tier One Risk Based Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets | 8.50% | 8.50%
Tier 1 capital, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | $ 164,397 | $ 158,177
Tier 1 capital to risk weighted assets, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | 8.00% | 8.00%
Common equity tier 1 capital | $ 210,672 | $ 212,315
Common equity tier 1 capital to risk-weighted assets | 10.25% | 10.74%
Common equity tier 1 capital, Minimum Required for Capital Adequacy Purposes | $ 92,473 | $ 88,974
Common equity tier 1 capital to risk-weighted assets, Minimum Required for Capital Adequacy Purposes | 4.50% | 4.50%
Common Equity Tier One Capital Required for Capital Adequacy Plus Capital Conservation Buffer | $ 143,847 | $ 138,405
Common Equity Tier One Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets | 7.00% | 7.00%
Common equity tier 1 capital, Minimum Required to Be Well Capitalized Under Prompt Corrective Action Requirements | $ 133,572 | $ 128,519
Common equity tier 1 capital to risk-weighted assets, Minimum Required to Be Well Capitalized Under Prompt Corrective Action Requirements | 6.50% | 6.50%
Tier 1 leverage capital | $ 210,672 | $ 212,315
Tier 1 leverage capital to average assets | 10.09% | 10.18%
Tier 1 leverage capital, Minimum Required for Capital Adequacy Purposes | $ 83,525 | $ 83,414
Tier 1 leverage capital to average assets, Minimum Required for Capital Adequacy Purposes | 4.00% | 4.00%
Tier One Leverage Capital Required for Capital Adequacy Plus Capital Conservation Buffer | $ 83,525 | $ 83,414
Tier One Leverage Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets | 4.00% | 4.00%
Tier 1 leverage capital, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | $ 104,406 | $ 104,268
Tier 1 leverage capital to average assets, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | 5.00% | 5.00%

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