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Stockholders' Equity and Regulatory Capital (Regulatory Capital Ratios) (Details) - USD ($) $ in Thousands | Dec. 31, 2019 | Dec. 31, 2018
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Compliance with Regulatory Capital Requirements under Banking Regulations |  |
Total Capital | $ 239,029 | $ 228,325
Total Capital to Risk-Weighted Assets | 12.01% | 11.85%
Total Capital, Minimum Required for Capital Adequacy Purposes | $ 159,185 | $ 154,080
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 | $ 208,930 | $ 190,192
Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets | 10.50% | 9.875%
Tier 1 capital | $ 194,456 | $ 181,175
Tier 1 Capital to Risk-Weighted Assets | 9.77% | 9.41%
Tier 1 Capital, Minimum Required for Capital Adequacy Purposes | $ 119,388 | $ 115,560
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 | $ 169,134 | $ 151,672
Tier One Risk Based Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets | 8.50% | 7.875%
Common Equity Tier One Capital | $ 184,409 | $ 171,142
Common Equity Tier One Capital to Risk-Weighted Assets | 9.27% | 8.89%
Common Equity Tier One Capital Required for Capital Adequacy | $ 89,541 | $ 86,670
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 | $ 139,286 | $ 122,782
Common Equity Tier One Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets | 7.70% | 6.375%
Tier 1 Capital | $ 194,456 | $ 181,175
Tier 1 Capital to Average Assets | 9.27% | 9.33%
Tier 1 Leverage Capital, Minimum Required for Capital Adequacy Purposes | $ 83,950 | $ 77,648
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 | $ 83,950 | $ 77,648
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 | $ 233,181 | $ 220,474
Total Capital to Risk-Weighted Assets | 11.79% | 11.49%
Total Capital, Minimum Required for Capital Adequacy Purposes | $ 158,177 | $ 153,456
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 | $ 207,607 | $ 189,422
Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets | 10.50% | 9.875%
Total Capital, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | $ 197,721 | $ 191,820
Total Capital to Risk-Weighted Assets, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | 10.00% | 10.00%
Tier 1 capital | $ 212,315 | $ 197,093
Tier 1 Capital to Risk-Weighted Assets | 10.74% | 10.27%
Tier 1 Capital, Minimum Required for Capital Adequacy Purposes | $ 118,633 | $ 115,092
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 | $ 168,063 | $ 151,058
Tier One Risk Based Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets | 8.50% | 7.875%
Tier 1 Capital, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | $ 158,177 | $ 153,456
Tier 1 Capital, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | 8.00% | 8.00%
Common Equity Tier One Capital | $ 212,315 | $ 197,093
Common Equity Tier One Capital to Risk-Weighted Assets | 10.74% | 10.27%
Common Equity Tier One Capital Required for Capital Adequacy | $ 88,974 | $ 86,319
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 | $ 138,405 | $ 122,285
Common Equity Tier One Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets | 7.00% | 6.375%
Common Equity Tier One Capital to be Well Capitalized | $ 128,519 | $ 124,683
Common Equity Tier One Capital Required to be Well Capitalized to Risk-Weighted Assets | 6.50% | 6.50%
Tier 1 Capital | $ 212,315 | $ 197,093
Tier 1 Capital to Average Assets | 10.18% | 10.20%
Tier 1 Leverage Capital, Minimum Required for Capital Adequacy Purposes | $ 83,414 | $ 77,301
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 | $ 83,414 | $ 77,301
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 | $ 104,268 | $ 96,626
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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