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Regulatory Capital (Regulatory Capital Ratios) (Details) $ in Thousands | Jun. 30, 2022 USD ($) | Dec. 31, 2021 USD ($)
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Compliance with Regulatory Capital Requirements under Banking Regulations |  |
Total capital | $ 309,573 | $ 281,745
Total capital to risk-weighted assets | 0.1156 | 0.1082
Total capital, Minimum Required for Capital Adequacy Purposes | $ 214,312 | $ 208,337
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 | $ 281,285 | $ 273,443
Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets | 10.50% | 10.50%
Tier 1 capital | $ 250,331 | $ 232,795
Tier 1 capital to risk-weighted assets | 0.0934 | 0.0894
Tier 1 capital, Minimum Required for Capital Adequacy Purposes | $ 160,734 | $ 156,253
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 | $ 227,707 | $ 221,358
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 | $ 238,339 | $ 222,719
Common equity tier 1 capital to risk-weighted assets | 8.90% | 8.55%
Common equity tier 1 capital, Minimum Required for Capital Adequacy Purposes | $ 120,551 | $ 117,190
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 | $ 187,523 | $ 182,295
Common Equity Tier One Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets | 7.00% | 7.00%
Tier 1 leverage capital | $ 250,331 | $ 232,795
Tier 1 leverage capital to average assets | 0.0919 | 0.0894
Tier 1 leverage capital, Minimum Required for Capital Adequacy Purposes | $ 108,923 | $ 104,145
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 | $ 108,923 | $ 104,145
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 | $ 301,151 | $ 280,448
Total capital to risk-weighted assets | 0.1125 | 0.1078
Total capital, Minimum Required for Capital Adequacy Purposes | $ 214,190 | $ 208,142
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 | $ 281,125 | $ 273,187
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 | $ 267,738 | $ 260,178
Total capital to risk-weighted assets, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | 0.1000 | 0.1000
Tier 1 capital | $ 276,184 | $ 255,286
Tier 1 capital to risk-weighted assets | 0.1032 | 0.0981
Tier 1 capital, Minimum Required for Capital Adequacy Purposes | $ 160,643 | $ 156,107
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 | $ 227,577 | $ 221,151
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 | $ 214,190 | $ 208,142
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 | $ 276,184 | $ 255,286
Common equity tier 1 capital to risk-weighted assets | 10.32% | 9.81%
Common equity tier 1 capital, Minimum Required for Capital Adequacy Purposes | $ 120,482 | $ 117,080
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 | $ 187,417 | $ 182,124
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 | $ 174,030 | $ 169,116
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 | $ 276,184 | $ 255,286
Tier 1 leverage capital to average assets | 0.1015 | 0.0981
Tier 1 leverage capital, Minimum Required for Capital Adequacy Purposes | $ 108,823 | $ 104,045
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 | $ 108,823 | $ 104,045
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 | $ 136,029 | $ 130,056
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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