XML 83 R77.htm IDEA: XBRL DOCUMENT v3.24.3

Commitments and Contingencies - Additional Information (Details) $ in Millions	Sep. 30, 2024 USD ($)
Commitments and Contingencies Disclosure [Abstract]
SBA loans, probability of future losses	$ 1.3

X

- Definition

SBA Loans, Probability of Future Losses

+ References

No definition available.

+ Details

Name:	fbiz_SBALoansProbabilityofFutureLosses
Namespace Prefix:	fbiz_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- References

No definition available.

+ Details

Name:	us-gaap_CommitmentsAndContingenciesDisclosureAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration