Regulatory Matters (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Common equity tier 1 capital, Minimum	4.50%
Common equity tier 1 capital, Well Capitalized	6.50%
Common equity tier 1 capital	12.85%	12.97%
Tier 1 capital, Minimum	6.00%
Tier 1 capital, Well Capitalized	8.00%
Tier 1 capital	13.09%	13.21%
Total capital, Minimum	8.00%
Total capital, Well Capitalized	10.00%
Total capital	14.93%	15.01%
Leverage ratio, Minimum	4.00%
Leverage ratio, Well Capitalized	5.00%
Leverage ratio	10.40%	10.34%
Common equity tier 1 capital	$ 1,283,068	$ 1,275,148
Tier 1 capital	1,307,318	1,299,398
Total capital	1,490,998	1,476,302
Risk-weighted assets	9,983,839	9,834,051
Average total assets for the leverage ratio	$ 12,570,521	$ 12,568,563
United Community Bank
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Common equity tier 1 capital	13.58%	14.87%
Tier 1 capital	13.58%	14.87%
Total capital	14.30%	15.54%
Leverage ratio	10.78%	11.63%
Common equity tier 1 capital	$ 1,351,820	$ 1,458,720
Tier 1 capital	1,351,820	1,458,720
Total capital	1,424,147	1,524,267
Risk-weighted assets	9,957,388	9,810,477
Average total assets for the leverage ratio	$ 12,538,532	$ 12,545,254

Common Equity Tier 1 Capital Required To Be Well Capitalized To Risk Weighted Assets.

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Common Equity Tier One Capital Required For Capital Adequacy To Risk Weighted Assets.

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The amount of total capital as defined in the regulations.

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The minimum Total risk based capital ratio (total capital divided by risk weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The Total risk based capital ratio (total capital divided by risk weighted assets) required to be categorized as "well capitalized", in the regulatory framework for prompt corrective action.

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Total Capital divided by risk weighted assets as defined in the regulations.

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Amount of Common Equity Tier One Risk-based Capital, as defined by regulatory framework.

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Percentage of Common Equity Tier One Risk-based Capital to total risk-weighted assets, as defined by regulatory framework.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The amount for the individual regulatory asset as itemized in a table of regulatory assets as of the end of the period.

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Amount of risk-weighted assets as calculated in accordance with U.S. Federal regulatory capital standards.

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The minimum amount of Tier 1 Leverage Capital for capital adequacy purposes divided by average assets as defined in the regulations.

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The amount of Tier 1 Leverage Capital required to be categorized as well capitalized divided by average assets as defined in the regulatory framework for prompt corrective action.

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Tier 1 Leverage Capital divided by average assets as defined in the regulations.

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Tier 1 Risk Based Capital as defined in the regulations.

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Tier 1 capital divided by risk weighted assets as defined by regulations.

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