Premises and Equipment - Schedule of Premises and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Accumulated depreciation and amortization	$ (105,033)	$ (95,989)
Total	88,709	94,355
Land
Property, Plant and Equipment [Line Items]
Premise and equipment, gross	9,195	9,195
Premises and equipment
Property, Plant and Equipment [Line Items]
Premise and equipment, gross	104,027	103,631
Furniture, fixtures, and equipment
Property, Plant and Equipment [Line Items]
Premise and equipment, gross	$ 80,520	$ 77,518