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Stockholders' Equity and Regulatory Capital (Regulatory Capital Ratios) (Details) - USD ($) $ in Thousands | Dec. 31, 2015 | Dec. 31, 2014
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Compliance with Regulatory Capital Requirements under Banking Regulations |  |
Total Capital | $ 189,163 | $ 173,263
Total Capital to Risk-Weighted Assets | 11.11% | 12.13%
Total Capital, Minimum Required for Capital Adequacy Purposes | $ 136,208 | $ 114,253
Total Capital to Risk-Weighted Assets, Minimum Required for Capital Adequacy Purposes | 8.00% | 8.00%
Tier 1 capital | $ 149,920 | $ 136,008
Tier 1 Capital to Risk-Weighted Assets | 8.81% | 9.52%
Tier 1 Capital, Minimum Required for Capital Adequacy Purposes | $ 102,156 | $ 57,127
Tier 1 Capital to Risk-Weighted Assets, Minimum Required for Capital Adequacy Purposes | 6.00% | 4.00%
Common Equity Tier One Capital | $ 139,920 |
Common Equity Tier One Capital to Risk-Weighted Assets | 8.22% |
Common Equity Tier One Capital Required for Capital Adequacy | $ 76,617 |
Common Equity Tier One Capital Required for Capital Adequacy to Risk-Weighted Assets | 4.50% |
Tier 1 Capital | $ 149,920 | $ 136,008
Tier 1 Capital to Average Assets | 8.63% | 8.71%
Tier 1 Leverage Capital, Minimum Required for Capital Adequacy Purposes | $ 69,466 | $ 62,490
Tier 1 Leverage Capital to Average Assets, Minimum Required for Capital Adequacy Purposes | 4.00% | 4.00%
First Business Bank |  |
Compliance with Regulatory Capital Requirements under Banking Regulations |  |
Total Capital | $ 141,388 | $ 131,411
Total Capital to Risk-Weighted Assets | 11.12% | 12.19%
Total Capital, Minimum Required for Capital Adequacy Purposes | $ 101,754 | $ 86,272
Total Capital to Risk-Weighted Assets, Minimum Required for Capital Adequacy Purposes | 8.00% | 8.00%
Total Capital, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | $ 127,193 | $ 107,841
Total Capital to Risk-Weighted Assets, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | 10.00% | 10.00%
Tier 1 capital | $ 128,852 | $ 118,907
Tier 1 Capital to Risk-Weighted Assets | 10.13% | 11.03%
Tier 1 Capital, Minimum Required for Capital Adequacy Purposes | $ 76,316 | $ 43,136
Tier 1 Capital to Risk-Weighted Assets, Minimum Required for Capital Adequacy Purposes | 6.00% | 4.00%
Tier 1 Capital, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | $ 101,754 | $ 64,704
Tier 1 Capital, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | 8.00% | 6.00%
Common Equity Tier One Capital | $ 128,852 |
Common Equity Tier One Capital to Risk-Weighted Assets | 10.13% |
Common Equity Tier One Capital Required for Capital Adequacy | $ 57,237 |
Common Equity Tier One Capital Required for Capital Adequacy to Risk-Weighted Assets | 4.50% |
Common Equity Tier One Capital to be Well Capitalized | $ 110,669 |
Common Equity Tier One Capital Required to be Well Capitalized to Risk-Weighted Assets | 6.50% |
Tier 1 Capital | $ 128,852 | $ 118,907
Tier 1 Capital to Average Assets | 10.44% | 10.13%
Tier 1 Leverage Capital, Minimum Required for Capital Adequacy Purposes | $ 49,359 | $ 46,960
Tier 1 Leverage Capital to Average Assets, Minimum Required for Capital Adequacy Purposes | 4.00% | 4.00%
Tier 1 Leverage Capital, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | $ 61,698 | $ 58,700
Tier 1 Leverage Capital to Average Assets, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | 5.00% | 5.00%
First Business Bank – Milwaukee |  |
Compliance with Regulatory Capital Requirements under Banking Regulations |  |
Total Capital | $ 20,931 | $ 19,128
Total Capital to Risk-Weighted Assets | 12.03% | 12.47%
Total Capital, Minimum Required for Capital Adequacy Purposes | $ 13,914 | $ 12,274
Total Capital to Risk-Weighted Assets, Minimum Required for Capital Adequacy Purposes | 8.00% | 8.00%
Total Capital, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | $ 17,392 | $ 15,343
Total Capital to Risk-Weighted Assets, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | 10.00% | 10.00%
Tier 1 capital | $ 19,172 | $ 17,641
Tier 1 Capital to Risk-Weighted Assets | 11.02% | 11.50%
Tier 1 Capital, Minimum Required for Capital Adequacy Purposes | $ 10,435 | $ 6,137
Tier 1 Capital to Risk-Weighted Assets, Minimum Required for Capital Adequacy Purposes | 6.00% | 4.00%
Tier 1 Capital, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | $ 13,914 | $ 9,206
Tier 1 Capital, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | 8.00% | 6.00%
Common Equity Tier One Capital | $ 19,172 |
Common Equity Tier One Capital to Risk-Weighted Assets | 11.02% |
Common Equity Tier One Capital Required for Capital Adequacy | $ 7,826 |
Common Equity Tier One Capital Required for Capital Adequacy to Risk-Weighted Assets | 4.50% |
Common Equity Tier One Capital to be Well Capitalized | $ 82,675 |
Common Equity Tier One Capital Required to be Well Capitalized to Risk-Weighted Assets | 6.50% |
Tier 1 Capital | $ 19,172 | $ 17,641
Tier 1 Capital to Average Assets | 7.81% | 7.90%
Tier 1 Leverage Capital, Minimum Required for Capital Adequacy Purposes | $ 9,821 | $ 8,935
Tier 1 Leverage Capital to Average Assets, Minimum Required for Capital Adequacy Purposes | 4.00% | 4.00%
Tier 1 Leverage Capital, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | $ 12,276 | $ 11,169
Tier 1 Leverage Capital to Average Assets, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | 5.00% | 5.00%
Alterra Bank |  |
Compliance with Regulatory Capital Requirements under Banking Regulations |  |
Total Capital | $ 30,300 |
Total Capital to Risk-Weighted Assets | 11.39% |
Total Capital, Minimum Required for Capital Adequacy Purposes | $ 21,279 |
Total Capital to Risk-Weighted Assets, Minimum Required for Capital Adequacy Purposes | 8.00% |
Total Capital, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | $ 26,598 |
Total Capital to Risk-Weighted Assets, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | 10.00% |
Tier 1 capital | $ 28,278 |
Tier 1 Capital to Risk-Weighted Assets | 10.63% |
Tier 1 Capital, Minimum Required for Capital Adequacy Purposes | $ 15,959 |
Tier 1 Capital to Risk-Weighted Assets, Minimum Required for Capital Adequacy Purposes | 6.00% |
Tier 1 Capital, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | $ 21,279 |
Tier 1 Capital, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | 8.00% |
Common Equity Tier One Capital | $ 28,278 |
Common Equity Tier One Capital to Risk-Weighted Assets | 10.63% |
Common Equity Tier One Capital Required for Capital Adequacy | $ 11,969 |
Common Equity Tier One Capital Required for Capital Adequacy to Risk-Weighted Assets | 4.50% |
Common Equity Tier One Capital to be Well Capitalized | $ 11,305 |
Common Equity Tier One Capital Required to be Well Capitalized to Risk-Weighted Assets | 6.50% |
Tier 1 Capital | $ 28,278 |
Tier 1 Capital to Average Assets | 9.89% |
Tier 1 Leverage Capital, Minimum Required for Capital Adequacy Purposes | $ 11,441 |
Tier 1 Leverage Capital to Average Assets, Minimum Required for Capital Adequacy Purposes | 4.00% |
Tier 1 Leverage Capital, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | $ 14,301 |
Tier 1 Leverage Capital to Average Assets, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | 5.00% |

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- Definition The minimum Tier One Capital Ratio (Tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=35709795&loc=SL5958568-112826 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=35709795&loc=SL5958570-112826 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=35709795&loc=d3e65071-112826 + Details
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