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Stockholders' Equity and Regulatory Capital (Regulatory Capital Ratios) (Details) - USD ($) $ in Thousands | Dec. 31, 2016 | Dec. 31, 2015
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Compliance with Regulatory Capital Requirements under Banking Regulations |  |
Total Capital | $ 204,117 | $ 189,163
Total Capital to Risk-Weighted Assets | 11.74% | 11.11%
Total Capital, Minimum Required for Capital Adequacy Purposes | $ 139,101 | $ 136,208
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 | $ 149,968 |
Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets | 8.625% |
Tier 1 capital | $ 160,964 | $ 149,920
Tier 1 Capital to Risk-Weighted Assets | 9.26% | 8.81%
Tier 1 Capital, Minimum Required for Capital Adequacy Purposes | $ 104,326 | $ 102,156
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 | $ 115,193 |
Tier One Risk Based Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets | 6.625% |
Common Equity Tier One Capital | $ 150,960 | $ 139,920
Common Equity Tier One Capital to Risk-Weighted Assets | 8.68% | 8.22%
Common Equity Tier One Capital Required for Capital Adequacy | $ 78,244 | $ 76,617
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 | $ 89,111 |
Common Equity Tier One Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets | 5.125% |
Tier 1 Capital | $ 160,964 | $ 149,920
Tier 1 Capital to Average Assets | 9.07% | 8.63%
Tier 1 Leverage Capital, Minimum Required for Capital Adequacy Purposes | $ 70,985 | $ 69,466
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 | $ 70,985 |
Tier One Leverage Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets | 4.00% |
First Business Bank |  |
Compliance with Regulatory Capital Requirements under Banking Regulations |  |
Total Capital | $ 147,811 | $ 141,388
Total Capital to Risk-Weighted Assets | 11.55% | 11.12%
Total Capital, Minimum Required for Capital Adequacy Purposes | $ 102,362 | $ 101,754
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 | $ 110,360 |
Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets | 8.625% |
Total Capital, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | $ 127,953 | $ 127,193
Total Capital to Risk-Weighted Assets, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | 10.00% | 10.00%
Tier 1 capital | $ 134,208 | $ 128,852
Tier 1 Capital to Risk-Weighted Assets | 10.49% | 10.13%
Tier 1 Capital, Minimum Required for Capital Adequacy Purposes | $ 76,772 | $ 76,316
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 | $ 84,769 |
Tier One Risk Based Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets | 6.625% |
Tier 1 Capital, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | $ 102,362 | $ 101,754
Tier 1 Capital, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | 8.00% | 8.00%
Common Equity Tier One Capital | $ 134,208 | $ 128,852
Common Equity Tier One Capital to Risk-Weighted Assets | 10.49% | 10.13%
Common Equity Tier One Capital Required for Capital Adequacy | $ 57,579 | $ 57,237
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 | $ 65,576 |
Common Equity Tier One Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets | 5.125% |
Common Equity Tier One Capital to be Well Capitalized | $ 83,170 | $ 110,669
Common Equity Tier One Capital Required to be Well Capitalized to Risk-Weighted Assets | 6.50% | 6.50%
Tier 1 Capital | $ 134,208 | $ 128,852
Tier 1 Capital to Average Assets | 10.40% | 10.44%
Tier 1 Leverage Capital, Minimum Required for Capital Adequacy Purposes | $ 51,600 | $ 49,359
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 | $ 51,600 |
Tier One Leverage Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets | 4.00% |
Tier 1 Leverage Capital, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | $ 64,500 | $ 61,698
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 | $ 24,347 | $ 20,931
Total Capital to Risk-Weighted Assets | 11.02% | 12.03%
Total Capital, Minimum Required for Capital Adequacy Purposes | $ 17,680 | $ 13,914
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 | $ 19,062 |
Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets | 8.625% |
Total Capital, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | $ 22,101 | $ 17,392
Total Capital to Risk-Weighted Assets, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | 10.00% | 10.00%
Tier 1 capital | $ 22,323 | $ 19,172
Tier 1 Capital to Risk-Weighted Assets | 10.10% | 11.02%
Tier 1 Capital, Minimum Required for Capital Adequacy Purposes | $ 13,260 | $ 10,435
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 | $ 14,642 |
Tier One Risk Based Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets | 6.625% |
Tier 1 Capital, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | $ 17,680 | $ 13,914
Tier 1 Capital, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | 8.00% | 8.00%
Common Equity Tier One Capital | $ 22,323 | $ 19,172
Common Equity Tier One Capital to Risk-Weighted Assets | 10.10% | 11.02%
Common Equity Tier One Capital Required for Capital Adequacy | $ 9,945 | $ 7,826
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 | $ 11,327 |
Common Equity Tier One Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets | 5.125% |
Common Equity Tier One Capital to be Well Capitalized | $ 14,365 | $ 82,675
Common Equity Tier One Capital Required to be Well Capitalized to Risk-Weighted Assets | 6.50% | 6.50%
Tier 1 Capital | $ 22,323 | $ 19,172
Tier 1 Capital to Average Assets | 9.15% | 7.81%
Tier 1 Leverage Capital, Minimum Required for Capital Adequacy Purposes | $ 9,758 | $ 9,821
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 | $ 9,758 |
Tier One Leverage Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets | 4.00% |
Tier 1 Leverage Capital, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | $ 12,198 | $ 12,276
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 | $ 31,699 | $ 30,300
Total Capital to Risk-Weighted Assets | 13.27% | 11.39%
Total Capital, Minimum Required for Capital Adequacy Purposes | $ 19,106 | $ 21,279
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 | $ 20,599 |
Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets | 8.625% |
Total Capital, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | $ 23,882 | $ 26,598
Total Capital to Risk-Weighted Assets, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | 10.00% | 10.00%
Tier 1 capital | $ 28,685 | $ 28,278
Tier 1 Capital to Risk-Weighted Assets | 12.01% | 10.63%
Tier 1 Capital, Minimum Required for Capital Adequacy Purposes | $ 14,329 | $ 15,959
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 | $ 15,822 |
Tier One Risk Based Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets | 6.625% |
Tier 1 Capital, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | $ 19,106 | $ 21,279
Tier 1 Capital, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | 8.00% | 8.00%
Common Equity Tier One Capital | $ 28,685 | $ 28,278
Common Equity Tier One Capital to Risk-Weighted Assets | 12.01% | 10.63%
Common Equity Tier One Capital Required for Capital Adequacy | $ 10,747 | $ 11,969
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 | $ 12,240 |
Common Equity Tier One Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets | 5.125% |
Common Equity Tier One Capital to be Well Capitalized | $ 15,524 | $ 11,305
Common Equity Tier One Capital Required to be Well Capitalized to Risk-Weighted Assets | 6.50% | 6.50%
Tier 1 Capital | $ 28,685 | $ 28,278
Tier 1 Capital to Average Assets | 10.58% | 9.89%
Tier 1 Leverage Capital, Minimum Required for Capital Adequacy Purposes | $ 10,842 | $ 11,441
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 | $ 10,842 |
Tier One Leverage Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets | 4.00% |
Tier 1 Leverage Capital, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | $ 13,552 | $ 14,301
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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- Definition The minimum amount of Tier 1 Risk Based Capital 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 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=35709795&loc=d3e65071-112826 Reference 2: 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 + Details
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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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- Definition The amount of Tier 1 Risk Based Capital required to be categorized as well capitalized 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 + Details
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