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Stockholders' Equity and Regulatory Capital (Regulatory Capital Ratios) (Details) $ in Thousands | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($)
--- | --- | ---
Compliance with Regulatory Capital Requirements under Banking Regulations |  |
Total Capital | $ 323,893 | $ 281,745
Total Capital to Risk-Weighted Assets | 0.1126 | 0.1082
Total Capital, Minimum Required for Capital Adequacy Purposes | $ 230,180 | $ 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 | $ 302,111 | $ 273,443
Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets | 10.50% | 10.50%
Tier 1 capital | $ 264,843 | $ 232,795
Tier 1 Capital to Risk-Weighted Assets | 0.0920 | 0.0894
Tier 1 Capital, Minimum Required for Capital Adequacy Purposes | $ 172,635 | $ 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 | $ 244,566 | $ 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 One Capital | $ 252,851 | $ 222,719
Common Equity Tier One Capital to Risk-Weighted Assets | 8.79% | 8.55%
Common Equity Tier One Capital Required for Capital Adequacy | $ 129,476 | $ 117,190
Common Equity Tier One Capital Required for Capital Adequacy to Risk-Weighted Assets | 4.50% | 4.50%
Common Equity Tier One Capital Required for Capital Adequacy Plus Capital Conservation Buffer | $ 201,407 | $ 182,295
Common Equity Tier One Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets | 7.00% | 7.00%
Tier 1 Capital | $ 264,843 | $ 232,795
Tier 1 Capital to Average Assets | 0.0917 | 0.0894
Tier 1 Leverage Capital, Minimum Required for Capital Adequacy Purposes | $ 115,464 | $ 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 | $ 115,464 | $ 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 | $ 323,021 | $ 280,448
Total Capital to Risk-Weighted Assets | 0.1122 | 0.1078
Total Capital, Minimum Required for Capital Adequacy Purposes | $ 230,367 | $ 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 | $ 302,357 | $ 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 | $ 287,959 | $ 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 | $ 298,312 | $ 255,286
Tier 1 Capital to Risk-Weighted Assets | 0.1036 | 0.0981
Tier 1 Capital, Minimum Required for Capital Adequacy Purposes | $ 172,775 | $ 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 | $ 244,765 | $ 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 | $ 230,367 | $ 208,142
Tier 1 Capital, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | 0.0800 | 0.0800
Common Equity Tier One Capital | $ 298,312 | $ 255,286
Common Equity Tier One Capital to Risk-Weighted Assets | 10.36% | 9.81%
Common Equity Tier One Capital Required for Capital Adequacy | $ 129,581 | $ 117,080
Common Equity Tier One Capital Required for Capital Adequacy to Risk-Weighted Assets | 4.50% | 4.50%
Common Equity Tier One Capital Required for Capital Adequacy Plus Capital Conservation Buffer | $ 201,571 | $ 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 One Capital to be Well Capitalized | $ 187,173 | $ 169,116
Common Equity Tier One Capital Required to be Well Capitalized to Risk-Weighted Assets | 6.50% | 6.50%
Tier 1 Capital | $ 298,312 | $ 255,286
Tier 1 Capital to Average Assets | 0.1034 | 0.0981
Tier 1 Leverage Capital, Minimum Required for Capital Adequacy Purposes | $ 115,402 | $ 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 | $ 115,402 | $ 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 | $ 144,252 | $ 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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