Premises and Equipment, Net (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	$ 1,084,085	$ 968,434
Less: Accumulated depreciation and amortization	329,757	297,265
Total premises and equipment, net	754,328	671,169
Depreciation and amortization expense	38,000	33,200	$ 31,500
Land
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	168,066	164,232
Buildings and leasehold improvements
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	646,153	586,968
Furniture, equipment, and computer software
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	243,926	201,055
Construction in progress
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	$ 25,940	$ 16,179

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.

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