XML 86 R75.htm IDEA: XBRL DOCUMENT
v3.25.0.1

Loans, Lease Receivables, and Allowance for Credit Losses - Schedule of Corporation Closely Monitors the Performance of Loans (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost basis | $ 14,014 | $ 882
Commercial and Industrial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost basis | 8,113 | 882
Commercial Real Estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost basis | 5,901 | 0
30-59 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost basis | 0 | 0
30-59 Days Past Due | Commercial and Industrial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost basis | 0 | 0
30-59 Days Past Due | Commercial Real Estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost basis | 0 | 0
60-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost basis | 0 | 0
60-89 Days Past Due | Commercial and Industrial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost basis | 0 | 0
60-89 Days Past Due | Commercial Real Estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost basis | 0 | 0
Greater Than 90 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost basis | 410 | 382
Greater Than 90 Days Past Due | Commercial and Industrial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost basis | 410 | 382
Greater Than 90 Days Past Due | Commercial Real Estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost basis | 0 | 0
Total Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost basis | 410 | 382
Total Past Due | Commercial and Industrial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost basis | 410 | 382
Total Past Due | Commercial Real Estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost basis | $ 0 | $ 0

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 310 -SubTopic 20 -Name Accounting Standards Codification -Section 40 -Paragraph 7 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481628/310-20-40-7 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481990/310-10-45-2 + Details
Name: | us-gaap_AccountsNotesAndLoansReceivableLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amortized cost excluding accrued interest, of financing receivable modified during period for debtor experiencing financial difficulty. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 42 -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481962/310-10-50-42 + Details
Name: | us-gaap_FinancingReceivableExcludingAccruedInterestModifiedPeriod
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=fbiz_CommercialandIndustrialLoansandLeasesReceivableMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialRealEstatePortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablesPeriodPastDueAxis=us-gaap_FinancingReceivables30To59DaysPastDueMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablesPeriodPastDueAxis=us-gaap_FinancingReceivables60To89DaysPastDueMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablesPeriodPastDueAxis=us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablesPeriodPastDueAxis=us-gaap_FinancialAssetPastDueMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |