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Regulatory Capital (Regulatory Capital Ratios) (Details) $ in Thousands | Sep. 30, 2020 USD ($) | Dec. 31, 2019 USD ($)
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Compliance with Regulatory Capital Requirements under Banking Regulations |  |
Total capital | $ 252,325 | $ 239,029
Total capital to risk-weighted assets | 0.1142 | 0.1201
Total capital, Minimum Required for Capital Adequacy Purposes | $ 176,728 | $ 159,185
Total capital to risk-weighted assets, Minimum Required for Capital Adequacy Purposes | 0.0800 | 0.0800
Capital Required for Capital Adequacy Plus Capital Conservation Buffer | $ 231,956 | $ 208,930
Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets | 10.50% | 10.50%
Tier 1 capital | $ 200,922 | $ 194,456
Tier 1 capital to risk-weighted assets | 0.0909 | 0.0977
Tier 1 capital, Minimum Required for Capital Adequacy Purposes | $ 132,546 | $ 119,388
Tier 1 capital to risk-weighted assets, Minimum Required for Capital Adequacy Purposes | 0.0600 | 0.0600
Tier One Risk Based Capital Required for Capital Adequacy Plus Capital Conservation Buffer | $ 187,774 | $ 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 | $ 190,864 | $ 184,409
Common equity tier 1 capital to risk-weighted assets | 8.64% | 9.27%
Common equity tier 1 capital, Minimum Required for Capital Adequacy Purposes | $ 99,410 | $ 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 | $ 154,637 | $ 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 | $ 200,922 | $ 194,456
Tier 1 leverage capital to average assets | 0.0804 | 0.0927
Tier 1 leverage capital, Minimum Required for Capital Adequacy Purposes | $ 99,940 | $ 83,950
Tier 1 leverage capital to average assets, Minimum Required for Capital Adequacy Purposes | 0.0400 | 0.0400
Tier One Leverage Capital Required for Capital Adequacy Plus Capital Conservation Buffer | $ 99,940 | $ 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 | $ 243,967 | $ 233,181
Total capital to risk-weighted assets | 0.1111 | 0.1179
Total capital, Minimum Required for Capital Adequacy Purposes | $ 175,634 | $ 158,177
Total capital to risk-weighted assets, Minimum Required for Capital Adequacy Purposes | 0.0800 | 0.0800
Capital Required for Capital Adequacy Plus Capital Conservation Buffer | $ 230,519 | $ 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 | $ 219,542 | $ 197,721
Total capital to risk-weighted assets, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | 0.1000 | 0.1000
Tier 1 capital | $ 216,469 | $ 212,315
Tier 1 capital to risk-weighted assets | 0.0986 | 0.1074
Tier 1 capital, Minimum Required for Capital Adequacy Purposes | $ 131,725 | $ 118,633
Tier 1 capital to risk-weighted assets, Minimum Required for Capital Adequacy Purposes | 0.0600 | 0.0600
Tier One Risk Based Capital Required for Capital Adequacy Plus Capital Conservation Buffer | $ 186,611 | $ 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 | $ 175,634 | $ 158,177
Tier 1 capital to risk weighted assets, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | 0.0800 | 0.0800
Common equity tier 1 capital | $ 216,469 | $ 212,315
Common equity tier 1 capital to risk-weighted assets | 9.86% | 10.74%
Common equity tier 1 capital, Minimum Required for Capital Adequacy Purposes | $ 98,794 | $ 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 | $ 153,680 | $ 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 | $ 142,702 | $ 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 | $ 216,469 | $ 212,315
Tier 1 leverage capital to average assets | 0.0872 | 0.1018
Tier 1 leverage capital, Minimum Required for Capital Adequacy Purposes | $ 99,347 | $ 83,414
Tier 1 leverage capital to average assets, Minimum Required for Capital Adequacy Purposes | 0.0400 | 0.0400
Tier One Leverage Capital Required for Capital Adequacy Plus Capital Conservation Buffer | $ 99,347 | $ 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 | $ 124,183 | $ 104,268
Tier 1 leverage capital to average assets, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | 0.0500 | 0.0500

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