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Stockholders' Equity and Regulatory Capital (Regulatory Capital Ratios) (Details) $ in Thousands | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($)
--- | --- | ---
Compliance with Regulatory Capital Requirements under Banking Regulations |  |
Total Capital | $ 258,607 | $ 239,029
Total Capital to Risk-Weighted Assets | 0.1125 | 0.1201
Total Capital, Minimum Required for Capital Adequacy Purposes | $ 183,965 | $ 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 | $ 241,454 | $ 208,930
Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets | 10.50% | 10.50%
Tier 1 capital | $ 206,104 | $ 194,456
Tier 1 Capital to Risk-Weighted Assets | 0.0896 | 0.0977
Tier 1 Capital, Minimum Required for Capital Adequacy Purposes | $ 137,974 | $ 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 | $ 195,463 | $ 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 One Capital | $ 196,042 | $ 184,409
Common Equity Tier One Capital to Risk-Weighted Assets | 8.53% | 9.27%
Common Equity Tier One Capital Required for Capital Adequacy | $ 103,480 | $ 89,541
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 | $ 160,970 | $ 139,286
Common Equity Tier One Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets | 7.00% | 7.00%
Tier 1 Capital | $ 206,104 | $ 194,456
Tier 1 Capital to Average Assets | 0.0799 | 0.0927
Tier 1 Leverage Capital, Minimum Required for Capital Adequacy Purposes | $ 103,228 | $ 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 | $ 103,228 | $ 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 | $ 251,116 | $ 233,181
Total Capital to Risk-Weighted Assets | 0.1097 | 0.1179
Total Capital, Minimum Required for Capital Adequacy Purposes | $ 183,053 | $ 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 | $ 240,257 | $ 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 | $ 228,816 | $ 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 | $ 222,500 | $ 212,315
Tier 1 Capital to Risk-Weighted Assets | 0.0972 | 0.1074
Tier 1 Capital, Minimum Required for Capital Adequacy Purposes | $ 137,290 | $ 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 | $ 194,494 | $ 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 | $ 183,053 | $ 158,177
Tier 1 Capital, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | 0.0800 | 0.0800
Common Equity Tier One Capital | $ 222,500 | $ 212,315
Common Equity Tier One Capital to Risk-Weighted Assets | 9.72% | 10.74%
Common Equity Tier One Capital Required for Capital Adequacy | $ 102,967 | $ 88,974
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 | $ 160,171 | $ 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 One Capital to be Well Capitalized | $ 148,731 | $ 128,519
Common Equity Tier One Capital Required to be Well Capitalized to Risk-Weighted Assets | 6.50% | 6.50%
Tier 1 Capital | $ 222,500 | $ 212,315
Tier 1 Capital to Average Assets | 0.0867 | 0.1018
Tier 1 Leverage Capital, Minimum Required for Capital Adequacy Purposes | $ 102,635 | $ 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 | $ 102,635 | $ 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 | $ 128,294 | $ 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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