Annual report pursuant to Section 13 and 15(d)

BORROWINGS (Narrative) (Details)

v2.4.1.9
BORROWINGS (Narrative) (Details) (USD $)
12 Months Ended 0 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Jan. 01, 2014
Remaining available balance for the federal funds lines $ 150,000,000ubsh_FederalFundsLinesAvailableBalance $ 93,500,000ubsh_FederalFundsLinesAvailableBalance    
Maximum collateral dependent line of credit with the FHLB 1,400,000,000us-gaap_FederalHomeLoanBankAdvancesGeneralDebtObligationsDisclosuresMaximumAmountAvailable 805,200,000us-gaap_FederalHomeLoanBankAdvancesGeneralDebtObligationsDisclosuresMaximumAmountAvailable    
Prepayment penalty 19,600,000us-gaap_PrepaymentFeesOnAdvancesNet      
Prepayment penalty amortization expense 1,800,000ubsh_DebtInstrumentAmortizationExpense 1,700,000ubsh_DebtInstrumentAmortizationExpense 612,000ubsh_DebtInstrumentAmortizationExpense  
Carrying value of the loans and securities pledged as collateral for FHLB 1,200,000,000us-gaap_FederalHomeLoanBankAdvancesGeneralDebtObligationsDisclosuresCollateralPledged1 1,100,000,000us-gaap_FederalHomeLoanBankAdvancesGeneralDebtObligationsDisclosuresCollateralPledged1    
Acquisitions, Prior To 2006 [Member]        
Number of bank acquisitions 2us-gaap_NumberOfBusinessesAcquired
/ us-gaap_StatementScenarioAxis
= ubsh_PriorToTwoThousandAndSixMember
     
Trust preferred capital notes principal balance 58,500,000us-gaap_ProceedsFromIssuanceOfTrustPreferredSecurities
/ us-gaap_StatementScenarioAxis
= ubsh_PriorToTwoThousandAndSixMember
     
Subordinated debt interest rate basis LIBOR plus 1.45%      
Remaining fair value discount on subordinated debt 652,000ubsh_RemainingFairValueDiscountOnSubordinatedDebt
/ us-gaap_StatementScenarioAxis
= ubsh_PriorToTwoThousandAndSixMember
     
Subordinated debt maturity date Apr. 01, 2016      
Subordinated debt 17,500,000us-gaap_SubordinatedLongTermDebt
/ us-gaap_StatementScenarioAxis
= ubsh_PriorToTwoThousandAndSixMember
     
LIBOR [Member] | Acquisitions, Prior To 2006 [Member]        
Three-month LIBOR rate plus 1.45%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
/ us-gaap_StatementScenarioAxis
= ubsh_PriorToTwoThousandAndSixMember
/ us-gaap_VariableRateAxis
= us-gaap_LondonInterbankOfferedRateLIBORMember
     
StellarOne Bank [Member]        
Trust preferred capital notes principal balance       32,000,000us-gaap_ProceedsFromIssuanceOfTrustPreferredSecurities
/ us-gaap_BusinessAcquisitionAxis
= ubsh_StellaroneBankMember
Remaining fair value premium on acquired FHLB advances 2,100,000ubsh_RemainingFairValueDiscountOnAcquiredFhlbAdvances
/ us-gaap_BusinessAcquisitionAxis
= ubsh_StellaroneBankMember
     
Remaining fair value discount on acquired trust preferred capital notes 7,200,000ubsh_RemainingFairValueDiscountOnAcquiredTrustPreferredCapitalNotes
/ us-gaap_BusinessAcquisitionAxis
= ubsh_StellaroneBankMember
     
Loans from Other Federal Home Loan Banks $ 70,000,000us-gaap_LoansFromOtherFederalHomeLoanBanks
/ us-gaap_BusinessAcquisitionAxis
= ubsh_StellaroneBankMember