XML 54 R62.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Investment Securities (Narrative) (Details) (USD $) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012
Schedule of Investments [Line Items] |  |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Losses | $ 108,000 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLosses | $ 8,361,000 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLosses |
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Losses | 13,864,000 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAggregateLosses | 25,488,000 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAggregateLosses |
Available-for-sale securities pledged as collateral |  | 192,000,000 us-gaap_AvailableForSaleSecuritiesPledgedAsCollateral | 175,000,000 us-gaap_AvailableForSaleSecuritiesPledgedAsCollateral
US Treasury Securities [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Nature | U.S. Government Treasuries – Available for Sale - Two U.S. government treasuries have been in an unrealized loss position for less than 12 months as of December 31, 2014. The securities are of the highest investment grade and the Corporation does not intend to sell them, and it is not more likely than not that the Corporation will be required to sell them before recovery of their amortized cost basis, which may be at maturity. Accordingly, management does not consider this investment to be other-than-temporarily impaired at December 31, 2014. There were no U.S. government treasuries in an unrealized loss position for 12 months or more. |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Less than One Year | 2 us-gaap_AvailableForSaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositionsLessThanOneYear / us-gaap_DebtSecurityAxis = us-gaap_USTreasurySecuritiesMember |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Greater than or Equal to One Year | 0 us-gaap_AvailableforsaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositionsGreaterThanOrEqualToOneYear / us-gaap_DebtSecurityAxis = us-gaap_USTreasurySecuritiesMember |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Losses | 11,000 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLosses / us-gaap_DebtSecurityAxis = us-gaap_USTreasurySecuritiesMember |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Losses | 0 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAggregateLosses / us-gaap_DebtSecurityAxis = us-gaap_USTreasurySecuritiesMember |  |
US Government Agencies [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Nature | U.S. Government Agencies – Available for Sale – There were no U.S. government agencies in an unrealized loss position for less than 12 months as of December 31, 2014. There were three U.S. government agencies in an unrealized loss position for 12 months or more. The securities are of the highest investment grade and the Corporation does not intend to sell them, and it is not more likely than not that the Corporation will be required to sell them before recovery of their amortized cost basis, which may be at maturity. Accordingly, management does not consider these investments to be other-than-temporarily impaired at December 31, 2014. |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Less than One Year | 0 us-gaap_AvailableForSaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositionsLessThanOneYear / us-gaap_DebtSecurityAxis = us-gaap_USGovernmentAgenciesDebtSecuritiesMember |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Greater than or Equal to One Year | 3 us-gaap_AvailableforsaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositionsGreaterThanOrEqualToOneYear / us-gaap_DebtSecurityAxis = us-gaap_USGovernmentAgenciesDebtSecuritiesMember |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Losses | 0 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLosses / us-gaap_DebtSecurityAxis = us-gaap_USGovernmentAgenciesDebtSecuritiesMember | 3,154,000 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLosses / us-gaap_DebtSecurityAxis = us-gaap_USGovernmentAgenciesDebtSecuritiesMember |
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Losses | 253,000 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAggregateLosses / us-gaap_DebtSecurityAxis = us-gaap_USGovernmentAgenciesDebtSecuritiesMember | 2,067,000 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAggregateLosses / us-gaap_DebtSecurityAxis = us-gaap_USGovernmentAgenciesDebtSecuritiesMember |
Held-to-maturity, Securities in Unrealized Loss Positions, Qualitative Disclosure, Nature | U.S. Government Agencies – Held to Maturity – There were no U.S. government agencies in an unrealized loss position at December 31, 2014. |  |
Residential mortgage-backed agencies [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Nature | Residential Mortgage-Backed Agencies – Available for Sale - There were no residential mortgage-backed agencies in an unrealized loss position for less than 12 months as of December 31, 2014. There were three residential mortgage-backed agency securities in an unrealized loss position for 12 months or more. The securities are of the highest investment grade and the Corporation does not intend to sell them, and it is not more likely than not that the Corporation will be required to sell the securities before recovery of their amortized cost basis, which may be at maturity. Accordingly, management does not consider these investments to be other-than-temporarily impaired at December 31, 2014. |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Less than One Year | 0 us-gaap_AvailableForSaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositionsLessThanOneYear / us-gaap_DebtSecurityAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Greater than or Equal to One Year | 3 us-gaap_AvailableforsaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositionsGreaterThanOrEqualToOneYear / us-gaap_DebtSecurityAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Losses | 0 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLosses / us-gaap_DebtSecurityAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember | 1,801,000 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLosses / us-gaap_DebtSecurityAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember |
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Losses | 412,000 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAggregateLosses / us-gaap_DebtSecurityAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember | 3,022,000 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAggregateLosses / us-gaap_DebtSecurityAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember |
Held-to-maturity, Securities in Unrealized Loss Positions, Qualitative Disclosure, Nature | Residential Mortgage-Backed Agencies – Held to Maturity – There were two residential mortgage-backed agencies in an unrealized loss position for less than 12 months as of December 31, 2014. The Corporation has the intent and ability to hold the investments to maturity. Accordingly, management does not consider these investments to be other-than-temporarily impaired at December 31, 2014. There were no residential mortgage-backed agencies in an unrealized loss position for 12 months or more. |  |
Commercial mortgage-backed agencies [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Nature | Commercial Mortgage-Backed Agencies – Available for Sale – There were two commercial mortgage-backed agencies in an unrealized loss position for less than 12 months as of December 31, 2014. There was one commercial mortgage-backed agency security in an unrealized loss position for 12 months or more. The securities are of the highest investment grade and the Corporation does not intend to sell them, and it is not more likely than not that the Corporation will be required to sell them before recovery of their amortized cost basis, which may be at maturity. Accordingly, management does not consider this investment to be other-than-temporarily impaired at December 31, 2014. |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Less than One Year | 2 us-gaap_AvailableForSaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositionsLessThanOneYear / us-gaap_DebtSecurityAxis = us-gaap_CommercialMortgageBackedSecuritiesMember |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Greater than or Equal to One Year | 1 us-gaap_AvailableforsaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositionsGreaterThanOrEqualToOneYear / us-gaap_DebtSecurityAxis = us-gaap_CommercialMortgageBackedSecuritiesMember |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Losses | 97,000 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLosses / us-gaap_DebtSecurityAxis = us-gaap_CommercialMortgageBackedSecuritiesMember | 1,134,000 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLosses / us-gaap_DebtSecurityAxis = us-gaap_CommercialMortgageBackedSecuritiesMember |
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Losses | 6,000 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAggregateLosses / us-gaap_DebtSecurityAxis = us-gaap_CommercialMortgageBackedSecuritiesMember | 0 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAggregateLosses / us-gaap_DebtSecurityAxis = us-gaap_CommercialMortgageBackedSecuritiesMember |
Held-to-maturity, Securities in Unrealized Loss Positions, Qualitative Disclosure, Nature | Commercial Mortgage-Backed Agencies – Held to Maturity – There were no commercial mortgage-backed agencies in an unrealized loss position at December 31, 2014. |  |
Collateralized mortgage obligations [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Nature | Collateralized Mortgage-Obligations – Available for Sale – There were no collateralized mortgage-obligation securities in an unrealized loss position for less than 12 months as of December 31, 2014. In addition, there were no collateralized mortgage-obligation securities in an unrealized loss position for 12 months or more. |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Greater than or Equal to One Year | 0 us-gaap_AvailableforsaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositionsGreaterThanOrEqualToOneYear / us-gaap_DebtSecurityAxis = us-gaap_MortgageBackedSecuritiesMember |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Losses | 0 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLosses / us-gaap_DebtSecurityAxis = us-gaap_MortgageBackedSecuritiesMember | 1,149,000 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLosses / us-gaap_DebtSecurityAxis = us-gaap_MortgageBackedSecuritiesMember |
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Losses | 0 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAggregateLosses / us-gaap_DebtSecurityAxis = us-gaap_MortgageBackedSecuritiesMember | 13,000 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAggregateLosses / us-gaap_DebtSecurityAxis = us-gaap_MortgageBackedSecuritiesMember |
Held-to-maturity, Securities in Unrealized Loss Positions, Qualitative Disclosure, Nature | Collateralized Mortgage-Obligations – Held to Maturity - There were no collateralized mortgage obligations in an unrealized loss position at December 31, 2014. |  |
Held-to-maturity, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | 0 us-gaap_HeldToMaturitySecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositions / us-gaap_DebtSecurityAxis = us-gaap_MortgageBackedSecuritiesMember |  |
Obligations of states and political subdivisions [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Nature | Obligations of State and Political Subdivisions – Available for Sale - No obligations of state and political subdivisions securities have been in an unrealized loss position for less than 12 months at December 31, 2014. There were four securities that have been in an unrealized loss position for 12 months or more. These investments are of investment grade as determined by the major rating agencies and management reviews the ratings of the underlying issuers and performs an in-depth credit analysis on the securities. Management believes that this portfolio is well-diversified throughout the United States, and all bonds continue to perform according to their contractual terms. The Corporation does not intend to sell these investments and it is not more likely than not that the Corporation will be required to sell the investments before recovery of their amortized cost basis, which may be at maturity. Accordingly, management does not consider these investments to be other-than-temporarily impaired at December 31, 2014. |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Less than One Year | 0 us-gaap_AvailableForSaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositionsLessThanOneYear / us-gaap_DebtSecurityAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Greater than or Equal to One Year | 4 us-gaap_AvailableforsaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositionsGreaterThanOrEqualToOneYear / us-gaap_DebtSecurityAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Losses | 0 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLosses / us-gaap_DebtSecurityAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember | 1,123,000 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLosses / us-gaap_DebtSecurityAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember |
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Losses | 260,000 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAggregateLosses / us-gaap_DebtSecurityAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember | 0 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAggregateLosses / us-gaap_DebtSecurityAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember |
Held-to-maturity, Securities in Unrealized Loss Positions, Qualitative Disclosure, Nature | Obligations of State and Political Subdivisions – Held to Maturity – No obligations of state and political subdivisions securities have been in an unrealized loss position for less than 12 months at December 31, 2014. There was one obligations of state and political subdivisions security that has been in an unrealized loss position for 12 months or more. This bond is a Tax Increment Fund (TIF) bond. Management performs an in-depth credit analysis on this security. The Corporation has the intent and ability to hold the investment to maturity. Accordingly, management does not consider this investment to be other-than-temporarily impaired at December 31, 2014. |  |
Collateralized Debt Obligations [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Nature | Collateralized Debt Obligations – Available for Sale - The $12.9 million in unrealized losses greater than 12 months at December 31, 2014 relates to 14 pooled trust preferred securities that are included in the CDO portfolio. See Note 24 for a discussion of the methodology used by management to determine the fair values of these securities. Based upon a review of credit quality and the cash flow tests performed by the independent third party, management determined that there were no securities that had credit-related non-cash OTTI charges during 2014. The unrealized losses on the remaining securities in the portfolio are primarily attributable to continued depression in market interest rates, marketability, liquidity and the current economic environment. |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | 17 us-gaap_AvailableforsaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositions1 / us-gaap_DebtSecurityAxis = us-gaap_CollateralizedDebtObligationsMember |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Greater than or Equal to One Year | 14 us-gaap_AvailableforsaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositionsGreaterThanOrEqualToOneYear / us-gaap_DebtSecurityAxis = us-gaap_CollateralizedDebtObligationsMember |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Losses | 0 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLosses / us-gaap_DebtSecurityAxis = us-gaap_CollateralizedDebtObligationsMember | 0 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLosses / us-gaap_DebtSecurityAxis = us-gaap_CollateralizedDebtObligationsMember |
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Losses | $ 12,933,000 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAggregateLosses / us-gaap_DebtSecurityAxis = us-gaap_CollateralizedDebtObligationsMember | $ 20,386,000 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAggregateLosses / us-gaap_DebtSecurityAxis = us-gaap_CollateralizedDebtObligationsMember |
Less Than 12 Months [Member] | Residential mortgage-backed agencies [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Held-to-maturity, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | 2 us-gaap_HeldToMaturitySecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositions / us-gaap_DebtSecurityAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember / us-gaap_RangeAxis = func_LessThan12MonthsMember |  |
Less Than 12 Months [Member] | Obligations of states and political subdivisions [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Held-to-maturity, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | 0 us-gaap_HeldToMaturitySecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositions / us-gaap_DebtSecurityAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember / us-gaap_RangeAxis = func_LessThan12MonthsMember |  |
Greater Than 12 Months [Member] | Residential mortgage-backed agencies [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Held-to-maturity, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | 0 us-gaap_HeldToMaturitySecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositions / us-gaap_DebtSecurityAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember / us-gaap_RangeAxis = func_GreaterThan12MonthsMember |  |
Greater Than 12 Months [Member] | Obligations of states and political subdivisions [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Held-to-maturity, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | 1 us-gaap_HeldToMaturitySecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositions / us-gaap_DebtSecurityAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember / us-gaap_RangeAxis = func_GreaterThan12MonthsMember |  |

X
- Definition Amount of unrealized loss on securities classified as available-for-sale that have been in a loss position for twelve months or longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563 + Details
Name: | us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAggregateLosses
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of unrealized loss on investments in available-for-sale securities that have been in a loss position for less than twelve months. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563 + Details
Name: | us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLosses
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Disclosure regarding factors used to determine that the impairment of securities not categorized as either held-to-maturity securities or trading securities (hence equal to available for sale securities) where cost exceeds fair value is not an other than temporary impairment (OTTI). This item contains disclosure of the nature of the available-for-sale investments determined to be temporarily impaired. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563 + Details
Name: | us-gaap_AvailableForSaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureNature
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of investment positions in available-for-sale investments in a continuous unrealized loss position for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563 + Details
Name: | us-gaap_AvailableforsaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositions1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of investment positions in available-for-sale investments that have been in a continuous unrealized loss position for greater than or equal to a year for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement. + References No definition available. + Details
Name: | us-gaap_AvailableforsaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositionsGreaterThanOrEqualToOneYear
Namespace Prefix: | us-gaap_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of investment positions in available-for-sale investments in a continuous unrealized loss position for less than one year or normal operating cycle, if longer, for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement. + References No definition available. + Details
Name: | us-gaap_AvailableForSaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositionsLessThanOneYear
Namespace Prefix: | us-gaap_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition The fair value of available-for-sale securities that serve as collateral for borrowings. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5086-111524 + Details
Name: | us-gaap_AvailableForSaleSecuritiesPledgedAsCollateral
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Disclosure regarding factors used to determine that the impairment of securities categorized as held-to-maturity where cost exceeds fair value is not an other than temporary impairment (OTTI). This item contains disclosure of the nature of the held-to-maturity investments determined to be temporarily impaired. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563 + Details
Name: | us-gaap_HeldToMaturitySecuritiesInUnrealizedLossPositionsQualitativeDisclosureNature
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Disclosure regarding factors used to determine that the impairment of securities categorized as held-to-maturity where cost exceeds fair value is not an other than temporary impairment (OTTI). This item contains disclosure of the number of investment positions in the held-to-maturity investments determined to be temporarily impaired. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563 + Details
Name: | us-gaap_HeldToMaturitySecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositions
Namespace Prefix: | us-gaap_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | us-gaap_ScheduleOfInvestmentsLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_DebtSecurityAxis=us-gaap_CollateralizedDebtObligationsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtSecurityAxis=us-gaap_CommercialMortgageBackedSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtSecurityAxis=us-gaap_MortgageBackedSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtSecurityAxis=us-gaap_ResidentialMortgageBackedSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtSecurityAxis=us-gaap_USGovernmentAgenciesDebtSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtSecurityAxis=us-gaap_USStatesAndPoliticalSubdivisionsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtSecurityAxis=us-gaap_USTreasurySecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RangeAxis=func_GreaterThan12MonthsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RangeAxis=func_LessThan12MonthsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |