XML 55 R45.htm IDEA: XBRL DOCUMENT
v3.10.0.1

Securities (Unrealized Losses Available for Sale) (Details) - USD ($) $ in Thousands | Jun. 30, 2018 | Dec. 31, 2017
--- | --- | ---
Fair Value |  |
Less than 12 Months | $ 90,602 | $ 74,446
12 Months or Longer | 34,648 | 37,474
Total | 125,250 | 111,920
Unrealized Losses |  |
Less than 12 Months | 1,910 | 565
12 Months or Longer | 1,399 | 935
Total | 3,309 | 1,500
U.S. government agency obligations - government-sponsored enterprises |  |
Fair Value |  |
Less than 12 Months | 4,975 |
12 Months or Longer | 0 |
Total | 4,975 |
Unrealized Losses |  |
Less than 12 Months | 17 |
12 Months or Longer | 0 |
Total | 17 |
Municipal obligations |  |
Fair Value |  |
Less than 12 Months | 3,681 | 6,132
12 Months or Longer | 2,588 | 2,755
Total | 6,269 | 8,887
Unrealized Losses |  |
Less than 12 Months | 41 | 43
12 Months or Longer | 60 | 39
Total | 101 | 82
Collateralized mortgage obligations - government issued |  |
Fair Value |  |
Less than 12 Months | 10,917 | 7,104
12 Months or Longer | 6,353 | 6,715
Total | 17,270 | 13,819
Unrealized Losses |  |
Less than 12 Months | 232 | 40
12 Months or Longer | 270 | 173
Total | 502 | 213
Collateralized mortgage obligations - government-sponsored enterprises |  |
Fair Value |  |
Less than 12 Months | 68,892 | 59,256
12 Months or Longer | 25,464 | 28,004
Total | 94,356 | 87,260
Unrealized Losses |  |
Less than 12 Months | 1,552 | 476
12 Months or Longer | 1,067 | 723
Total | 2,619 | 1,199
Other securities |  |
Fair Value |  |
Less than 12 Months | 2,137 | 1,954
12 Months or Longer | 243 | 0
Total | 2,380 | 1,954
Unrealized Losses |  |
Less than 12 Months | 68 | 6
12 Months or Longer | 2 | 0
Total | $ 70 | $ 6

X
- Definition Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss1 + References No definition available. + Details
Name: | fbiz_AvailableforsaleSecuritiesContinuousUnrealizedLossPosition12MonthsorLongerAggregateLoss1
Namespace Prefix: | fbiz_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss1 + References No definition available. + Details
Name: | fbiz_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionAggregateLoss1
Namespace Prefix: | fbiz_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss1 + References No definition available. + Details
Name: | fbiz_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionLessthan12MonthsAggregateLoss1
Namespace Prefix: | fbiz_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- References No definition available. + Details
Name: | us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAggregateLossesAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563 + Details
Name: | us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- References No definition available. + Details
Name: | us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValueAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for less than twelve months. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27337-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563 + Details
Name: | us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for twelve months or longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27337-111563 + Details
Name: | us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_NontaxableMunicipalBondsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_GovernmentNationalMortgageAssociationCertificatesAndObligationsGNMAMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=fbiz_OtherDebtandEquitySecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |