Stockholders' Equity and Regulatory Requirements (Details) - Schedule of Compliance with Regulatory Capital Requirements - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets	1.79%
Parent Company [Member]
Tier One Leverage Capital	$ 425,407	$ 390,205
Tier One Leverage Capital to Average Assets	8.92%	9.29%
Tier One Leverage Capital Required for Capital Adequacy	$ 190,728	$ 168,048
Tier One Leverage Capital Required for Capital Adequacy to Average Assets	4.00%	4.00%
Tier One Leverage Capital Required to be Well Capitalized
Tier One Leverage Capital Required to be Well Capitalized to Average Assets
CET One Risk Based Capital	$ 420,252	$ 385,050
CET One Risk Based Capital to Risk Weighted Assets	9.15%	9.74%
CET One Risk Based Capital Required for Capital Adequacy	$ 206,742	$ 177,967
CET One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets	4.50%	4.50%
CET One Risk Based Capital Required to be Well Capitalized
CET One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets
Tier One Risk Based Capital	$ 425,407	$ 390,205
Tier One Risk Based Capital to Risk Weighted Assets	9.26%	9.87%
Tier One Risk Based Capital Required for Capital Adequacy	$ 275,656	$ 237,289
Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets	6.00%	6.00%
Tier One Risk Based Capital Required to be Well Capitalized
Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets
Capital	$ 507,155	$ 465,949
Capital to Risk Weighted Assets	11.04%	11.78%
Capital Required for Capital Adequacy	$ 367,542	$ 316,386
Capital Required for Capital Adequacy to Risk Weighted Assets	8.00%	8.00%
Capital Required to be Well Capitalized
Capital Required to be Well Capitalized to Risk Weighted Assets
Union Center National Bank [Member]
Tier One Leverage Capital	$ 468,899	$ 434,067
Tier One Leverage Capital to Average Assets	9.84%	10.34%
Tier One Leverage Capital Required for Capital Adequacy	$ 190,665	$ 167,996
Tier One Leverage Capital Required for Capital Adequacy to Average Assets	4.00%	4.00%
Tier One Leverage Capital Required to be Well Capitalized	$ 238,332	$ 209,995
Tier One Leverage Capital Required to be Well Capitalized to Average Assets	5.00%	5.00%
CET One Risk Based Capital	$ 468,899	$ 434,067
CET One Risk Based Capital to Risk Weighted Assets	10.21%	10.98%
CET One Risk Based Capital Required for Capital Adequacy	$ 206,721	$ 177,944
CET One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets	4.50%	4.50%
CET One Risk Based Capital Required to be Well Capitalized	$ 298,597	$ 257,030
CET One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets	6.50%	6.50%
Tier One Risk Based Capital	$ 468,899	$ 434,067
Tier One Risk Based Capital to Risk Weighted Assets	10.21%	10.98%
Tier One Risk Based Capital Required for Capital Adequacy	$ 275,628	$ 237,258
Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets	6.00%	6.00%
Tier One Risk Based Capital Required to be Well Capitalized	$ 367,504	$ 316,344
Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets	8.00%	8.00%
Capital	$ 500,647	$ 459,811
Capital to Risk Weighted Assets	10.90%	11.63%
Capital Required for Capital Adequacy	$ 367,504	$ 316,344
Capital Required for Capital Adequacy to Risk Weighted Assets	8.00%	8.00%
Capital Required to be Well Capitalized	$ 459,379	$ 395,430
Capital Required to be Well Capitalized to Risk Weighted Assets	10.00%	10.00%

CET one risk based capital.

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CET One Risk Based Capital Required for Capital Adequacy.

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CET One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets.

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CET One Risk Based Capital Required to be Well Capitalized.

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CET One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets.

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CET One Risk Based 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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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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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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