Annual report pursuant to Section 13 and 15(d)

EMPLOYEE BENEFITS AND SHARE BASED COMPENSATION (Summary of Stock Option Activity) (Details)

v2.4.1.9
EMPLOYEE BENEFITS AND SHARE BASED COMPENSATION (Summary of Stock Option Activity) (Details) (USD $)
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Dec. 31, 2011
Summary of stock option activity        
Number of Stock Options, Outstanding beginning balance 402,946us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber 500,578us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber 422,750us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber  
Weighted Average Exercise Price, Outstanding beginning balance $ 16.48us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice $ 16.92us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice $ 17.70us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice  
Number of Stock Options, Outstanding ending balance 389,269us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber 402,946us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber 500,578us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber  
Weighted Average Exercise Price, Outstanding ending balance $ 16.69us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice $ 16.48us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice $ 16.92us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice  
Number of Stock Options, Granted 0us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod   131,657us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod  
Weighted Average Exercise Price, Granted     $ 14.40us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice  
Number of Stock Options, Exercised (75,282)us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised (50,119)us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised (2,376)us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised  
Weighted Average Exercise Price, Exercised $ 17.28us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice $ 18.45us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice $ 12.11us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice  
Number of Stock Options, Forfeited (62,612)us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod (47,513)us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod (51,453)us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod  
Weighted Average Exercise Price, Forfeited $ 23.00us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice $ 19.04us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice $ 17.11us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice  
Number of Stock Options, Exercisable 262,213us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber 200,904us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber 218,825us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber 184,985us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber
Weighted Average Exercise Price, Options exercisable $ 18.04us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice $ 18.96us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice $ 20.59us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice $ 22.28us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice
StellarOne Bank [Member]        
Summary of stock option activity        
Number of Stock Options, Exercisable 124,217us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber
/ us-gaap_BusinessAcquisitionAxis
= ubsh_StellaroneBankMember
     
Weighted Average Exercise Price, Options exercisable $ 20.88us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice
/ us-gaap_BusinessAcquisitionAxis
= ubsh_StellaroneBankMember
     
Number of options converted 124,217ubsh_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsConverted
/ us-gaap_BusinessAcquisitionAxis
= ubsh_StellaroneBankMember
     
Weighted Average Exercise Price, Options converted 20.88ubsh_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsConvertedWeightedAverageExercisePrice
/ us-gaap_BusinessAcquisitionAxis
= ubsh_StellaroneBankMember