Name:	ucbi_ServicingAssetAtFairValueAdditionsAbstract
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Amount of additions from origination of servicing assets capitalized upon sale.

No definition available.

Name:	ucbi_ServicingAssetAtFairValueOriginationOfServicingAssetCapitalizedUponSale
Namespace Prefix:	ucbi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- References

No definition available.

Name:	ucbi_ServicingAssetAtFairValueSubtractionsAbstract
Namespace Prefix:	ucbi_
Data Type:	xbrli:stringItemType
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Amount of increase (decrease) in fair value from changes in the assumptions or model used to calculate the fair value of a contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

No definition available.

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

Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6469459&loc=d3e122501-111745

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=116651436&loc=d3e122625-111746

Name:	us-gaap_ServicingAssetAtFairValueAmount
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Period Type:	instant

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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

Decrease in servicing assets subsequently measured at fair value resulting from conveyance of servicing rights to unrelated parties.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=116651436&loc=d3e122625-111746

Name:	us-gaap_ServicingAssetAtFairValueDisposals
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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Period Type:	duration

Amount of increase (decrease) in fair value from changes classified as other for a contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 3
-Subparagraph (a)(5)
-URI http://asc.fasb.org/extlink&oid=116651436&loc=d3e122625-111746