Stockholders' Equity and Regulatory Requirements (Details) - Schedule of Compliance with Regulatory Capital Requirements - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets	1.99%
Parent Company [Member]
Tier One Leverage Capital	$ 478,876	$ 425,407
Tier One Leverage Capital to Average Assets	9.34%	8.92%
Tier One Leverage Capital Required for Capital Adequacy	$ 204,995	$ 190,728
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	$ 473,721	$ 420,252
CET One Risk Based Capital to Risk Weighted Assets	9.75%	9.15%
CET One Risk Based Capital Required for Capital Adequacy	$ 218,585	$ 206,742
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	$ 478,876	$ 425,407
Tier One Risk Based Capital to Risk Weighted Assets	9.86%	9.26%
Tier One Risk Based Capital Required for Capital Adequacy	$ 291,446	$ 275,656
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	$ 638,830	$ 507,155
Capital to Risk Weighted Assets	13.15%	11.04%
Capital Required for Capital Adequacy	$ 388,595	$ 367,542
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	$ 552,311	$ 468,899
Tier One Leverage Capital to Average Assets	10.78%	9.84%
Tier One Leverage Capital Required for Capital Adequacy	$ 204,973	$ 190,665
Tier One Leverage Capital Required for Capital Adequacy to Average Assets	4.00%	4.00%
Tier One Leverage Capital Required to be Well Capitalized	$ 256,217	$ 238,332
Tier One Leverage Capital Required to be Well Capitalized to Average Assets	5.00%	5.00%
CET One Risk Based Capital	$ 552,311	$ 468,899
CET One Risk Based Capital to Risk Weighted Assets	11.37%	10.21%
CET One Risk Based Capital Required for Capital Adequacy	$ 218,589	$ 206,721
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	$ 315,740	$ 298,597
CET One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets	6.50%	6.50%
Tier One Risk Based Capital	$ 552,311	$ 468,899
Tier One Risk Based Capital to Risk Weighted Assets	11.37%	10.21%
Tier One Risk Based Capital Required for Capital Adequacy	$ 291,452	$ 275,628
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	$ 388,603	$ 367,504
Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets	8.00%	8.00%
Capital	$ 619,515	$ 500,647
Capital to Risk Weighted Assets	12.75%	10.90%
Capital Required for Capital Adequacy	$ 388,603	$ 367,504
Capital Required for Capital Adequacy to Risk Weighted Assets	8.00%	8.00%
Capital Required to be Well Capitalized	$ 485,754	$ 459,379
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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