XML 76 R70.htm IDEA: XBRL DOCUMENT
v3.24.3

Deposits - Composition Of Deposits (Details) - USD ($) $ in Thousands | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2024 | Dec. 31, 2023
Deposits |  |
Deposits | $ 2,969,947 | $ 2,796,779
Average balance, deposits | $ 2,854,096 | $ 2,444,438
Deposits, weighted average interest rate during the period | 3.45% | 2.92%
Non-interest-bearing transaction accounts |  |
Deposits |  |
Deposits | $ 428,012 | $ 445,376
Average balance, deposits | $ 440,182 | $ 453,930
Deposits, weighted average interest rate during the period | 0.00% | 0.00%
Interest-bearing transaction accounts |  |
Deposits |  |
Deposits | $ 930,252 | $ 895,319
Average balance, deposits | $ 869,511 | $ 689,500
Deposits, weighted average interest rate during the period | 3.93% | 3.44%
Money market accounts |  |
Deposits |  |
Deposits | $ 817,129 | $ 711,245
Average balance, deposits | $ 809,593 | $ 681,336
Deposits, weighted average interest rate during the period | 4.05% | 3.25%
Certificates of deposit |  |
Deposits |  |
Deposits | $ 207,337 | $ 287,131
Average balance, deposits | $ 246,267 | $ 273,387
Deposits, weighted average interest rate during the period | 4.65% | 4.10%
Wholesale deposits |  |
Deposits |  |
Deposits | $ 587,217 | $ 457,708
Average balance, deposits | $ 488,543 | $ 346,285
Deposits, weighted average interest rate during the period | 4.08% | 4.14%

X
- Definition Average Balance, Deposits + References No definition available. + Details
Name: | fbiz_AverageBalanceDeposits
Namespace Prefix: | fbiz_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition [Line Items] for Deposit [Table] + References No definition available. + Details
Name: | fbiz_DepositLineItems
Namespace Prefix: | fbiz_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Deposits, Weighted Average Interest Rate During the Period + References No definition available. + Details
Name: | fbiz_DepositsWeightedAverageInterestRateDuringthePeriod
Namespace Prefix: | fbiz_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(12)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1 + Details
Name: | us-gaap_Deposits
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | fbiz_DepositTypeAxis=fbiz_NoninterestbearingTransactionAccountsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | fbiz_DepositTypeAxis=fbiz_InterestbearingTransactionAccountsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | fbiz_DepositTypeAxis=fbiz_MoneyMarketAccountsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | fbiz_DepositTypeAxis=fbiz_NonbrokeredCertificatesofDepositMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | fbiz_DepositTypeAxis=fbiz_BrokeredCertificatesofDepositMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |