Annual report pursuant to Section 13 and 15(d)

REGULATORY MATTERS AND CAPITAL (Narrative) (Details)

v2.4.1.9
REGULATORY MATTERS AND CAPITAL (Narrative) (Details) (USD $)
In Millions, unless otherwise specified
 12 Months Ended 23 Months Ended 0 Months Ended
Dec. 31, 2014
Dec. 31, 2015
Jan. 01, 2015
Jan. 01, 2019
Dec. 31, 2013
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]          
Tier 1 capital ratio of risk-weighted assets 4.00%us-gaap_TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssets       4.00%us-gaap_TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssets
Capital ratio of risk-weighted assets 8.00%us-gaap_CapitalRequiredForCapitalAdequacyToRiskWeightedAssets       8.00%us-gaap_CapitalRequiredForCapitalAdequacyToRiskWeightedAssets
Leverage ratio of total assets 4.00%us-gaap_TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssets       4.00%us-gaap_TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssets
Stock repurchased and retired, shares 2.1us-gaap_StockRepurchasedAndRetiredDuringPeriodShares        
Stock repurchase program, remaining authorized amount $ 12.5us-gaap_StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount        
Current Rule [Member]          
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]          
Tier 1 capital ratio of risk-weighted assets 4.00%us-gaap_TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssets
/ us-gaap_StatementScenarioAxis
= ubsh_CurrentRuleMember 		       
Subsequent Event [Member]          
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]          
Stock repurchase program, amount authorized   65.0us-gaap_StockRepurchaseProgramAuthorizedAmount
/ us-gaap_SubsequentEventTypeAxis
= us-gaap_SubsequentEventMember 		     
Subsequent Event [Member] | Future 2015 Rule [Member]          
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]          
New Common Equity Tier 1 capital ratio of risk-weighted assets     4.50%ubsh_NewCommonEquityTierOneRiskBasedCapitalToRiskWeightedAssets
/ us-gaap_StatementScenarioAxis
= ubsh_Future2015RuleMember
/ us-gaap_SubsequentEventTypeAxis
= us-gaap_SubsequentEventMember 		   
Tier 1 capital ratio of risk-weighted assets     6.00%us-gaap_TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssets
/ us-gaap_StatementScenarioAxis
= ubsh_Future2015RuleMember
/ us-gaap_SubsequentEventTypeAxis
= us-gaap_SubsequentEventMember 		   
Capital ratio of risk-weighted assets     8.00%us-gaap_CapitalRequiredForCapitalAdequacyToRiskWeightedAssets
/ us-gaap_StatementScenarioAxis
= ubsh_Future2015RuleMember
/ us-gaap_SubsequentEventTypeAxis
= us-gaap_SubsequentEventMember 		   
Leverage ratio of total assets     4.00%us-gaap_TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssets
/ us-gaap_StatementScenarioAxis
= ubsh_Future2015RuleMember
/ us-gaap_SubsequentEventTypeAxis
= us-gaap_SubsequentEventMember 		   
Subsequent Event [Member] | Future 2019 Rule [Member]          
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]          
Leverage ratio of total assets       4.00%us-gaap_TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssets
/ us-gaap_StatementScenarioAxis
= ubsh_Future2019RuleMember
/ us-gaap_SubsequentEventTypeAxis
= us-gaap_SubsequentEventMember 		 
New capital requirements phase-in period       4 years  
Capital conservation buffer rate       2.50%ubsh_CapitalConservationBufferRate
/ us-gaap_StatementScenarioAxis
= ubsh_Future2019RuleMember
/ us-gaap_SubsequentEventTypeAxis
= us-gaap_SubsequentEventMember 		 
Annual incremental capital conversion buffer rate       0.625%ubsh_AnnualIncrementalCapitalConversionBufferRate
/ us-gaap_StatementScenarioAxis
= ubsh_Future2019RuleMember
/ us-gaap_SubsequentEventTypeAxis
= us-gaap_SubsequentEventMember 		 
Subsequent Event [Member] | Minimum [Member] | Future 2019 Rule [Member]          
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]          
New Common Equity Tier 1 capital ratio of risk-weighted assets       7.00%ubsh_NewCommonEquityTierOneRiskBasedCapitalToRiskWeightedAssets
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
/ us-gaap_StatementScenarioAxis
= ubsh_Future2019RuleMember
/ us-gaap_SubsequentEventTypeAxis
= us-gaap_SubsequentEventMember 		 
Tier 1 capital ratio of risk-weighted assets       8.50%us-gaap_TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssets
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
/ us-gaap_StatementScenarioAxis
= ubsh_Future2019RuleMember
/ us-gaap_SubsequentEventTypeAxis
= us-gaap_SubsequentEventMember 		 
Capital ratio of risk-weighted assets       10.50%us-gaap_CapitalRequiredForCapitalAdequacyToRiskWeightedAssets
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
/ us-gaap_StatementScenarioAxis
= ubsh_Future2019RuleMember
/ us-gaap_SubsequentEventTypeAxis
= us-gaap_SubsequentEventMember 		 
Subsequent Event [Member] | Maximum [Member]          
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]          
Stock repurchase program, amount authorized   $ 65.0us-gaap_StockRepurchaseProgramAuthorizedAmount
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
/ us-gaap_SubsequentEventTypeAxis
= us-gaap_SubsequentEventMember