Stockholders' Equity and Regulatory Requirements (Details) - Schedule of Compliance with Regulatory Capital Requirements - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets	2.37%
Parent Company [Member]
Tier One Leverage Capital	$ 694,895	$ 563,464
Tier One Leverage Capital to Average Assets	9.51%	9.54%
Tier One Leverage Capital Required for Capital Adequacy	$ 292,349	$ 236,259
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	$ 689,740	$ 558,309
CET One Risk Based Capital to Risk Weighted Assets	10.79%	9.95%
CET One Risk Based Capital Required for Capital Adequacy	$ 287,746	$ 252,439
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	$ 694,895	$ 563,464
Tier One Risk Based Capital to Risk Weighted Assets	10.87%	10.04%
Tier One Risk Based Capital Required for Capital Adequacy	$ 383,661	$ 336,586
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	$ 964,121	$ 726,757
Capital to Risk Weighted Assets	15.08%	12.96%
Capital Required for Capital Adequacy	$ 511,548	$ 448,781
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	$ 776,430	$ 637,824
Tier One Leverage Capital to Average Assets	10.64%	10.81%
Tier One Leverage Capital Required for Capital Adequacy	$ 291,958	$ 236,188
Tier One Leverage Capital Required for Capital Adequacy to Average Assets	4.00%	4.00%
Tier One Leverage Capital Required to be Well Capitalized	$ 364,947	$ 295,235
Tier One Leverage Capital Required to be Well Capitalized to Average Assets	5.00%	5.00%
CET One Risk Based Capital	$ 776,430	$ 637,824
CET One Risk Based Capital to Risk Weighted Assets	12.24%	11.37%
CET One Risk Based Capital Required for Capital Adequacy	$ 285,473	$ 252,432
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	$ 412,349	$ 364,625
CET One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets	6.50%	6.50%
Tier One Risk Based Capital	$ 776,430	$ 637,824
Tier One Risk Based Capital to Risk Weighted Assets	12.24%	11.37%
Tier One Risk Based Capital Required for Capital Adequacy	$ 380,630	$ 336,577
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	$ 507,507	$ 448,769
Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets	8.00%	8.00%
Capital	$ 887,906	$ 708,367
Capital to Risk Weighted Assets	14.00%	12.63%
Capital Required for Capital Adequacy	$ 507,507	$ 448,769
Capital Required for Capital Adequacy to Risk Weighted Assets	8.00%	8.00%
Capital Required to be Well Capitalized	$ 634,384	$ 560,961
Capital Required to be Well Capitalized to Risk Weighted Assets	10.00%	10.00%