Premises and Equipment - Components and Depreciation and Amortization Expenses (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Components of premises and equipment
Premises and equipment	$ 537,498	$ 571,602
Less: Accumulated depreciation and amortization	257,143	253,154
Net book value	280,355	318,448
Depreciation and amortization expenses	15,318	15,831	$ 15,952
Occupancy
Components of premises and equipment
Depreciation and amortization expenses	9,192	9,149	9,231
Equipment expense
Components of premises and equipment
Depreciation and amortization expenses	6,126	6,682	$ 6,721
Buildings
Components of premises and equipment
Premises and equipment	294,051	295,286
Furniture and equipment
Components of premises and equipment
Premises and equipment	92,276	95,824
Land
Components of premises and equipment
Premises and equipment	97,955	113,720
Leasehold improvements
Components of premises and equipment
Premises and equipment	$ 53,216	$ 66,772

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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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.

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