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Regulatory Capital (Regulatory Capital Ratios) (Details) - USD ($) $ in Thousands | Jun. 30, 2015 | Dec. 31, 2014
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Compliance with Regulatory Capital Requirements under Banking Regulations |  |
Total capital | $ 181,281 | $ 173,263
Total capital to risk-weighted assets | 11.11% | 12.13%
Total capital, Minimum Required for Capital Adequacy Purposes | $ 130,502 | $ 114,253
Total capital to risk-weighted assets, Minimum Required for Capital Adequacy Purposes | 8.00% | 8.00%
Tier 1 capital | $ 143,156 | $ 136,008
Tier 1 capital to risk-weighted assets | 8.78% | 9.52%
Tier 1 capital, Minimum Required for Capital Adequacy Purposes | $ 97,877 | $ 57,127
Tier 1 capital to risk-weighted assets, Minimum Required for Capital Adequacy Purposes | 6.00% | 4.00%
Common equity tier 1 capital | $ 133,156 |
Common equity tier 1 capital to risk-weighted assets | 8.16% |
Common equity tier 1 capital, Minimum Required for Capital Adequacy Purposes | $ 73,407 |
Common equity tier 1 capital to risk-weighted assets, Minimum Required for Capital Adequacy Purposes | 4.50% |
Tier 1 capital | $ 143,156 | $ 136,008
Tier 1 leverage capital to average assets | 8.66% | 8.71%
Tier 1 leverage capital, Minimum Required for Capital Adequacy Purposes | $ 5,326 | $ 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 | $ 135,519 | $ 131,411
Total capital to risk-weighted assets | 11.23% | 12.19%
Total capital, Minimum Required for Capital Adequacy Purposes | $ 96,523 | $ 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 | $ 120,654 | $ 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 | $ 123,424 | $ 118,907
Tier 1 capital to risk-weighted assets | 10.23% | 11.03%
Tier 1 capital, Minimum Required for Capital Adequacy Purposes | $ 72,393 | $ 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 | $ 96,523 | $ 64,704
Tier 1 capital to risk weighted assets, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | 8.00% | 6.00%
Common equity tier 1 capital | $ 123,424 |
Common equity tier 1 capital to risk-weighted assets | 10.23% |
Common equity tier 1 capital, Minimum Required for Capital Adequacy Purposes | $ 54,294 |
Common equity tier 1 capital to risk-weighted assets, Minimum Required for Capital Adequacy Purposes | 4.50% |
Common equity tier 1 capital, Minimum Required to Be Well Capitalized Under Prompt Corrective Action Requirements | $ 106,033 |
Common equity tier 1 capital to risk-weighted assets, Minimum Required to Be Well Capitalized Under Prompt Corrective Action Requirements | 6.50% |
Tier 1 capital | $ 123,424 | $ 118,907
Tier 1 leverage capital to average assets | 10.55% | 10.13%
Tier 1 leverage capital, Minimum Required for Capital Adequacy Purposes | $ 4,937 | $ 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 | $ 6,171 | $ 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 | $ 19,404 | $ 19,128
Total capital to risk-weighted assets | 11.27% | 12.47%
Total capital, Minimum Required for Capital Adequacy Purposes | $ 13,779 | $ 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 | $ 17,223 | $ 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 | $ 17,746 | $ 17,641
Tier 1 capital to risk-weighted assets | 10.30% | 11.50%
Tier 1 capital, Minimum Required for Capital Adequacy Purposes | $ 10,334 | $ 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 | $ 13,779 | $ 9,206
Tier 1 capital to risk weighted assets, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | 8.00% | 6.00%
Common equity tier 1 capital | $ 17,746 |
Common equity tier 1 capital to risk-weighted assets | 10.30% |
Common equity tier 1 capital, Minimum Required for Capital Adequacy Purposes | $ 7,751 |
Common equity tier 1 capital to risk-weighted assets, Minimum Required for Capital Adequacy Purposes | 4.50% |
Common equity tier 1 capital, Minimum Required to Be Well Capitalized Under Prompt Corrective Action Requirements | $ 78,425 |
Common equity tier 1 capital to risk-weighted assets, Minimum Required to Be Well Capitalized Under Prompt Corrective Action Requirements | 6.50% |
Tier 1 capital | $ 17,746 | $ 17,641
Tier 1 leverage capital to average assets | 7.46% | 7.90%
Tier 1 leverage capital, Minimum Required for Capital Adequacy Purposes | $ 710 | $ 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 | $ 887 | $ 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 | $ 27,979 | $ 22,657
Total capital to risk-weighted assets | 10.79% | 10.90%
Total capital, Minimum Required for Capital Adequacy Purposes | $ 20,748 | $ 16,628
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 | $ 25,935 | $ 20,785
Total capital to risk-weighted assets, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | 10.00% | 10.00%
Tier 1 capital | $ 26,533 | $ 22,320
Tier 1 capital to risk-weighted assets | 10.23% | 10.74%
Tier 1 capital, Minimum Required for Capital Adequacy Purposes | $ 15,561 | $ 8,314
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 | $ 20,748 | $ 12,471
Tier 1 capital to risk weighted assets, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | 8.00% | 6.00%
Common equity tier 1 capital | $ 26,533 |
Common equity tier 1 capital to risk-weighted assets | 10.23% |
Common equity tier 1 capital, Minimum Required for Capital Adequacy Purposes | $ 11,671 |
Common equity tier 1 capital to risk-weighted assets, Minimum Required for Capital Adequacy Purposes | 4.50% |
Common equity tier 1 capital, Minimum Required to Be Well Capitalized Under Prompt Corrective Action Requirements | $ 11,195 |
Common equity tier 1 capital to risk-weighted assets, Minimum Required to Be Well Capitalized Under Prompt Corrective Action Requirements | 6.50% |
Tier 1 capital | $ 26,533 | $ 22,320
Tier 1 leverage capital to average assets | 10.00% | 9.01%
Tier 1 leverage capital, Minimum Required for Capital Adequacy Purposes | $ 1,061 | $ 9,910
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 | $ 1,327 | $ 12,388
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 amount of total capital as defined in the regulations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 948 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6490092&loc=d3e47304-110998 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=35709795&loc=d3e65071-112826 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 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 948 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=6490092&loc=d3e47080-110998 + Details
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- Definition The minimum Total risk based capital ratio (total 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 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=35709795&loc=d3e65071-112826 Reference 3: 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 + Details
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- Definition The amount of Total Capital required to be categorized as well as 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 -URI http://asc.fasb.org/extlink&oid=35709795&loc=SL5958568-112826 + Details
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- Definition Tier 1 Leverage Capital as defined in the regulations. Also called Core Capital. + 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 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=35709795&loc=d3e65071-112826 + Details
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- Definition The minimum amount of Tier 1 Leverage Capital for capital adequacy purposes divided by average assets as defined in the regulations. + 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 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=35709795&loc=d3e65071-112826 Reference 3: 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 + Details
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- Definition The amount of Tier 1 Leverage 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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- Definition The amount of Tier 1 Leverage Capital required to be categorized as well capitalized divided by average assets as defined in 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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- Definition Tier 1 Risk Based Capital as defined in the regulations. + 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 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=35709795&loc=d3e65071-112826 + Details
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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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- Definition The Tier 1 capital ratio (Tier 1 capital divided by risk weighted assets) 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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