Loan Receivable Amount Sba Loan Guarantee Approval Received

No definition available.

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Namespace Prefix:	func_
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- Definition

Number Of Paycheck Protection Program Loan Applications Approved

+ References

No definition available.

+ Details

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- Definition

Number Of States With Reported Covid Nineteen Cases

+ References

No definition available.

+ Details

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- Definition

Paycheck Protection Program Loan Interest Rate

+ References

No definition available.

+ Details

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Namespace Prefix:	func_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Paycheck Protection Program Loan Maturity Term

+ References

No definition available.

+ Details

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- Definition

Paycheck Protection Program Loan Sba Processing Fees Percent

+ References

No definition available.

+ Details

Name:	func_PaycheckProtectionProgramLoanSbaProcessingFeesPercent
Namespace Prefix:	func_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Paycheck Protection Program Loans Sba Guarantee Percent

+ References

No definition available.

+ Details

Name:	func_PaycheckProtectionProgramLoansSbaGuaranteePercent
Namespace Prefix:	func_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage Of Allowance For Loan Losses

+ References

No definition available.

+ Details

Name:	func_PercentageOfAllowanceForLoanLosses
Namespace Prefix:	func_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage Of Businesses Receiving Paycheck Protection Program Loans With Less Than 10 Employees

+ References

No definition available.

+ Details

Name:	func_PercentageOfBusinessesReceivingPaycheckProtectionProgramLoansWithLessThan10Employees
Namespace Prefix:	func_
Data Type:	num:percentItemType
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Period Type:	duration

- Definition

Percentage Of Paycheck Protection Program Loans Approved Under 100000

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Percentage Of Proceeds Customers Use For Payroll Costs To Qualify For Sba Loan Forgiveness

+ References

No definition available.

+ Details

Name:	func_PercentageOfProceedsCustomersUseForPayrollCostsToQualifyForSbaLoanForgiveness
Namespace Prefix:	func_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of increase (decrease) of allowance reserve for credit loss.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(d))
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-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
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-URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74567-122707

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Amount, before allowance and fees, of loans and leases receivable. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=118952595&loc=d3e4428-111522

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- 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

No definition available.

+ Details

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Significant Event (Narrative) (Details) $ in Thousands		3 Months Ended	12 Months Ended
Significant Event (Narrative) (Details) $ in Thousands	May 01, 2020 USD ($) contract	Mar. 31, 2020 USD ($) state contract	Dec. 31, 2019 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Significant Event [Line Items]
Allowance for loan losses		$ 15,012	$ 12,537	$ 11,548	$ 11,047
Percentage of allowance for loan losses			1.19%
COVID-19 [Member]
Significant Event [Line Items]
Number of states with COVID-19 reported cases \| state		50
Increase in allowance for loan losses		$ 2,500
Allowance for loan losses		$ 15,000
Percentage of allowance for loan losses		1.42%
COVID-19 [Member] \| CARES Act [Member]
Significant Event [Line Items]
Number of Paycheck Protection Program loan applications approved \| contract		428
Loan receivable amount SBA PPP loan approval received		$ 111,000
COVID-19 [Member] \| CARES Act [Member] \| Subsequent Event [Member]
Significant Event [Line Items]
Number of Paycheck Protection Program loan applications approved \| contract	492
Loan receivable amount SBA PPP loan approval received	$ 29,000
Percentage of PPP loans approved under $100,000 in size	73.00%
Percentage of businesses receiving PPP oans with less than 10 employees	65.00%
PPP loans SBA guarantee percent	100.00%
PPP loans maturity term	2 years
PPP loans interest rate	1.00%
Loan processing fees	$ 3,500
COVID-19 [Member] \| CARES Act [Member] \| Maximum [Member] \| Subsequent Event [Member]
Significant Event [Line Items]
PPP loans SBA processing fees, percent	5.00%
COVID-19 [Member] \| CARES Act [Member] \| Minimum [Member] \| Subsequent Event [Member]
Significant Event [Line Items]
Number of Paycheck Protection Program loan applications approved \| contract	920
Loan receivable amount SBA PPP loan approval received	$ 140,000
Percentage of proceeds customers use for payroll costs to qualify for SBA loan forgiveness	75.00%
PPP loans SBA processing fees, percent	1.00%