Bank Premises and Equipment, Net - Bank Premises and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Bank premises and equipment, gross	$ 74,186	$ 68,470
Less: Accumulated depreciation and amortization	46,007	39,794
Bank premises and equipment, net	28,179	28,676
Leasehold Improvements [Member]
Bank premises and equipment, gross	44,984	41,304
Equipment and Furniture [Member]
Bank premises and equipment, gross	$ 29,202	$ 27,166

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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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.

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