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           ACQUISITIONS (Schedule of Effect of Amortization and Accretion Related to Acquisition) (Details) (USD $) 
        In Thousands, unless otherwise specified  | 
        12 Months Ended | |
|---|---|---|
| 
           Dec. 31, 2014 
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           Dec. 31, 2013 
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| ACQUISITIONS [Abstract] | ||
| Loans | $ 586ubsh_NetImpactOfLoansAccretionRelatedToAcquisition | $ 2,728ubsh_NetImpactOfLoansAccretionRelatedToAcquisition | 
| Core deposit intangibles | (9,795)ubsh_NetImpactOfCoreDepositIntangibleAmortizationRelatedToAcquisition | (3,831)ubsh_NetImpactOfCoreDepositIntangibleAmortizationRelatedToAcquisition | 
| Borrowings | 550ubsh_NetImpactOfBorrowingsAccretionRelatedToAcquisition | (489)ubsh_NetImpactOfBorrowingsAccretionRelatedToAcquisition | 
| Time deposits | 8,914ubsh_NetImpactOfTimeDepositsAccretionRelatedToAcquisition | 7ubsh_NetImpactOfTimeDepositsAccretionRelatedToAcquisition | 
| Net impact to income before taxes | $ 255ubsh_NetImpactOfAmortizationAndAccretionRelatedToAcquisition | $ (1,585)ubsh_NetImpactOfAmortizationAndAccretionRelatedToAcquisition | 
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- Definition 
          Net impact of amortization and accretion related to acquisition. No definition available. 
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- Definition 
          The impact of borrowings accretion (amortization) related to acquisitions on income before taxes No definition available. 
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- Definition 
          The impact of core deposit intangibles accretion (amortization) related to acquisitions on income before taxes. No definition available. 
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- Definition 
          The impact of loans accretion (amortization) related to acquisitions on income before taxes. No definition available. 
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- Definition 
          The impact of time deposits accretion (amortization) related to acquisitions on income before taxes. No definition available. 
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- Details 
          
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