LOANS AND ALLOWANCE FOR LOAN LOSSES (Impaired Loans Individually Evaluated for Impairment by Segment) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Recorded Investment
Loans without a specific allowance	$ 32,281		$ 31,553
Loans with a specific allowance	25,074		9,596
Total impaired loans	57,355		41,149
Unpaid Principal Balance
Loans without a specific allowance	34,107		33,723
Loans with a specific allowance	26,155		10,240
Total impaired loans	60,262		43,963
Related Allowance	2,515		816
Average Investment	58,535	$ 78,207
Interest Income Recognized	425	912
Construction and Land Development
Recorded Investment
Loans without a specific allowance	11,290		13,877
Loans with a specific allowance	6,011		1,395
Unpaid Principal Balance
Loans without a specific allowance	11,775		14,353
Loans with a specific allowance	6,018		1,404
Related Allowance	729		107
Average Investment	17,179	30,569
Interest Income Recognized	139	484
Commercial Real Estate - Owner Occupied
Recorded Investment
Loans without a specific allowance	6,120		5,886
Loans with a specific allowance	639		646
Unpaid Principal Balance
Loans without a specific allowance	6,285		6,042
Loans with a specific allowance	639		646
Related Allowance	3		4
Average Investment	6,793	16,510
Interest Income Recognized	64	157
Commercial Real Estate - Non-Owner Occupied
Recorded Investment
Loans without a specific allowance	2,825		1,399
Loans with a specific allowance	8,691		2,809
Unpaid Principal Balance
Loans without a specific allowance	2,825		1,399
Loans with a specific allowance	8,739		2,809
Related Allowance	745		474
Average Investment	11,540	4,214
Interest Income Recognized	108	41
Multifamily Real Estate
Unpaid Principal Balance
Average Investment	0	3,817
Interest Income Recognized	0	60
Commercial & Industrial
Recorded Investment
Loans without a specific allowance	949		648
Loans with a specific allowance	5,151		857
Unpaid Principal Balance
Loans without a specific allowance	949		890
Loans with a specific allowance	5,442		880
Related Allowance	617		14
Average Investment	6,830	3,663
Interest Income Recognized	36	37
Residential 1-4 Family
Recorded Investment
Loans without a specific allowance	9,541		8,496
Loans with a specific allowance	3,243		3,335
Unpaid Principal Balance
Loans without a specific allowance	10,515		9,518
Loans with a specific allowance	3,414		3,535
Related Allowance	393		200
Average Investment	13,047	15,301
Interest Income Recognized	73	106
Auto
Recorded Investment
Loans with a specific allowance	393		169
Unpaid Principal Balance
Loans with a specific allowance	506		235
Related Allowance	1		1
Average Investment	477	218
Interest Income Recognized	1	0
HELOC
Recorded Investment
Loans without a specific allowance	1,443		1,017
Loans with a specific allowance	757		323
Unpaid Principal Balance
Loans without a specific allowance	1,535		1,094
Loans with a specific allowance	881		433
Related Allowance	20		15
Average Investment	2,366	2,933
Interest Income Recognized	4	21
Consumer and all other
Recorded Investment
Loans without a specific allowance	113		230
Loans with a specific allowance	189		62
Unpaid Principal Balance
Loans without a specific allowance	223		427
Loans with a specific allowance	516		298
Related Allowance	7		$ 1
Average Investment	303	982
Interest Income Recognized	$ 0	$ 6

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5258-111524

+ Details

Name:	us-gaap_ImpairedFinancingReceivableAverageRecordedInvestment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

+ References

+ Details

Name:	us-gaap_ImpairedFinancingReceivableInterestIncomeAccrualMethod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953550-111524

+ Details

Name:	us-gaap_ImpairedFinancingReceivableRecordedInvestment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- References

No definition available.

+ Details

Name:	us-gaap_ImpairedFinancingReceivableRecordedInvestmentAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of allowance for credit losses related to recorded investment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524

+ Details

Name:	us-gaap_ImpairedFinancingReceivableRelatedAllowance
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses.

+ References

+ Details

Name:	us-gaap_ImpairedFinancingReceivableUnpaidPrincipalBalance
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- References

No definition available.

+ Details

Name:	us-gaap_ImpairedFinancingReceivableUnpaidPrincipalBalanceAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of investment in impaired financing receivables for which there is no related allowance for credit losses.

+ References

+ Details

Name:	us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of unpaid principal balance of impaired financing receivables for which there is no related allowance for credit losses.

+ References

+ Details

Name:	us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of investment in impaired financing receivables for which there is a related allowance for credit losses.

+ References

+ Details

Name:	us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Unpaid principal balance of impaired financing receivables for which there is a related allowance for credit losses.

+ References

+ Details

Name:	us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_ConstructionLoansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=ubsh_CommercialRealEstateOwnerOccupiedMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=ubsh_CommercialRealEstateNonOwnerOccupiedMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_MultifamilyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=ubsh_CommercialAndIndustrialMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_ResidentialRealEstateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_AutomobileLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_HomeEquityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=ubsh_OtherConsumerMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: