Regulatory Capital Requirements - Actual and Statutory Required Capital Amounts and Ratios (Detail) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
United Community [Member]
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Total capital (to risk-weighted assets), Actual Amount	$ 293,814	$ 277,817
Tier 1 capital (to risk-weighted assets), Actual Amount	274,154	258,869
Common equity Tier 1 capital (to risk-weighted assets), Actual Amount	274,154	258,869
Tier 1 capital (to average assets), Actual Amount	$ 274,154	$ 258,869
Total capital (to risk-weighted assets), Actual Ratio	15.66%	18.38%
Tier 1 capital (to risk-weighted assets), Actual Ratio	14.61%	17.13%
Common equity Tier 1 capital (to risk-weighted assets), Actual Ratio	14.61%	17.13%
Tier 1 capital (to average assets), Actual Ratio	10.76%	11.98%
Total capital (to risk-weighted assets), Minimum Capital Requirements Amount	$ 173,548	$ 130,369
Tier 1 capital (to risk-weighted assets), Minimum Capital Requirements Amount	136,024	100,139
Common equity Tier 1 capital (to risk-weighted assets), Minimum Capital Requirements Amount	107,881	77,466
Tier 1 capital (to average assets), Minimum Capital Requirements Amount	$ 101,870	$ 86,425
Total capital (to risk-weighted assets), Minimum Capital Requirements Ratio	9.25%	8.625%
Tier 1 capital (to risk-weighted assets), Minimum Capital Requirements Ratio	7.25%	6.625%
Common equity Tier 1 capital (to risk-weighted assets), Minimum Capital Requirements Ratio	5.75%	5.125%
Tier 1 capital (to average assets), Minimum Capital Requirements Ratio	4.00%	4.00%
Home Savings [Member]
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Total capital (to risk-weighted assets), Actual Amount	$ 277,583	$ 248,861
Tier 1 capital (to risk-weighted assets), Actual Amount	257,947	229,938
Common equity Tier 1 capital (to risk-weighted assets), Actual Amount	257,947	229,938
Tier 1 capital (to average assets), Actual Amount	$ 257,947	$ 229,938
Total capital (to risk-weighted assets), Actual Ratio	14.83%	16.47%
Tier 1 capital (to risk-weighted assets), Actual Ratio	13.78%	15.22%
Common equity Tier 1 capital (to risk-weighted assets), Actual Ratio	13.78%	15.22%
Tier 1 capital (to average assets), Actual Ratio	10.14%	10.65%
Total capital (to risk-weighted assets), Minimum Capital Requirements Amount	$ 173,129	$ 130,292
Tier 1 capital (to risk-weighted assets), Minimum Capital Requirements Amount	135,695	100,079
Common equity Tier 1 capital (to risk-weighted assets), Minimum Capital Requirements Amount	107,621	77,420
Tier 1 capital (to average assets), Minimum Capital Requirements Amount	$ 101,794	$ 86,360
Total capital (to risk-weighted assets), Minimum Capital Requirements Ratio	9.25%	8.625%
Tier 1 capital (to risk-weighted assets), Minimum Capital Requirements Ratio	7.25%	6.625%
Common equity Tier 1 capital (to risk-weighted assets), Minimum Capital Requirements Ratio	5.75%	5.125%
Tier 1 capital (to average assets), Minimum Capital Requirements Ratio	4.00%	4.00%
Total capital (to risk-weighted assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	$ 187,166	$ 151,063
Tier 1 capital (to risk-weighted assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	149,733	120,850
Common equity Tier 1 capital (to risk-weighted assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	121,658	98,191
Tier 1 capital (to average assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	$ 127,242	$ 107,950
Total capital (to risk-weighted assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio	10.00%	10.00%
Tier 1 capital (to risk-weighted assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio	8.00%	8.00%
Common equity Tier 1 capital (to risk-weighted assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio	6.50%	6.50%
Tier 1 capital (to average assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio	5.00%	5.00%

Common equity tier one capital required for capital adequacy to risk weighted assets.

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Common equity tier one capital required to be well capitalized to risk weighted assets.

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Common equity tier one capital to risk weighted assets.

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The amount of total capital as defined in the regulations.

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The minimum amount of Total Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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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 amount of Total Capital required to be categorized as well as capitalized 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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Amount of Common Equity Tier 1 Risk-based Capital required to be categorized as adequately capitalized under regulatory framework for prompt corrective action.

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Amount of Common Equity Tier 1 Risk-based Capital required to be categorized as well-capitalized under regulatory framework for prompt corrective action.

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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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Tier 1 Leverage Capital as defined in the regulations. Also called Core Capital.

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The minimum amount of Tier 1 Leverage Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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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 under the regulatory framework for prompt corrective action.

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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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The minimum amount of Tier 1 Risk Based Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The minimum Tier One Capital Ratio (Tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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-Publisher FASB
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The amount of Tier 1 Risk Based Capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action.

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The Tier 1 capital ratio (Tier 1 capital divided by risk weighted assets) required to be categorized as "well capitalized" under the regulatory framework for prompt corrective action.

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

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