Premises and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment, Net, by Type [Abstract]
Premises and equipment, gross	$ 126,877	$ 125,396
Less accumulated depreciation and amortization	(84,876)	(81,350)
Premises and equipment, net	42,001	44,046
Depreciation and amortization of premises and equipment	3,500	3,800	$ 3,800
Land and Buildings [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Premises and equipment, gross	80,959	80,552
Leasehold Improvements [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Premises and equipment, gross	4,805	4,805
Furniture, Fixtures, and Equipment [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Premises and equipment, gross	40,615	39,964
Construction in Progress [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Premises and equipment, gross	$ 498	$ 75

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

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