PARENT COMPANY FINANCIAL INFORMATION (Narrative) (Details) - Parent Company $ in Millions	Dec. 31, 2017 USD ($)
Aggregate amount of unrestricted funds	$ 100.4
Aggregate amount of unrestricted funds percentage	9.60%

Percentage of aggregate amount of unrestricted funds available for transfer to the Parent Company from the Bank to consolidated net assets.

No definition available.

Name:	ubsh_PercentageOfAggregateAmountOfUnrestrictedFundsAvailableToConsolidatedNetAssets
Namespace Prefix:	ubsh_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant