XML 77 R68.htm IDEA: XBRL DOCUMENT v3.22.2

Borrowings - Schedule of Available Unused Lines of Credit (Parenthetical) (Details) - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021
Debt Disclosure [Abstract]
Federal Home Loan Bank, advances, general debt obligations, disclosures, collateral pledged	$ 73.2	$ 66.6
Collateral exposure with FHLB in form of advances	40.0	40.0
Collateral pledged in excess available to utilize additional credit	$ 33.2	$ 26.6

X

- Definition

Amount of collateral pledged in excess available to utilize additional credit.

+ References

No definition available.

+ Details

Name:	fusb_FederalHomeLoanBankAdvancesGeneralDebtObligationsDisclosuresExcessOfCollateralAvailableToUtilizeAdditionalCredit
Namespace Prefix:	fusb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- References

No definition available.

+ Details

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

X

- Definition

Amount of advances from the Federal Home Loan Bank (FHLB).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

+ Details

Name:	us-gaap_FederalHomeLoanBankAdvancesBranchOfFHLBBankAmountOfAdvancesByBranch
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Definition

Amount of the collateral pledged in support of federal home loan bank advances outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (d)
-URI https://asc.fasb.org/extlink&oid=123599511&loc=d3e64711-112823

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

+ Details

Name:	us-gaap_FederalHomeLoanBankAdvancesGeneralDebtObligationsDisclosuresCollateralPledged1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant