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Premises and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
Premises and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Premises and equipment
Total	$ 836,774	$ 843,960
Less accumulated depreciation	(334,215)	(324,763)
Net premises and equipment	502,559	519,197
Depreciation expense charged to operations	28,900	28,200	$ 29,400
Capitalized implementation costs related to internal use software	0
Land
Premises and equipment
Total	132,703	132,717
Buildings and leasehold improvements
Premises and equipment
Total	$ 418,010	401,989
Buildings and leasehold improvements \| Minimum
Premises and equipment
Useful Life	15 years
Buildings and leasehold improvements \| Maximum
Premises and equipment
Useful Life	40 years
Equipment and furnishings
Premises and equipment
Total	$ 177,697	201,153
Equipment and furnishings \| Minimum
Premises and equipment
Useful Life	3 years
Equipment and furnishings \| Maximum
Premises and equipment
Useful Life	10 years
Lease right of use assets
Premises and equipment
Total	$ 95,835	100,331
Construction in process
Premises and equipment
Total	$ 12,529	7,770
Computer software
Premises and equipment
Useful Life	36 months
Total	$ 43,400	24,600
Depreciation expense charged to operations	4,600	4,900	$ 4,900
Unamortized balance remaining	$ 18,400	$ 4,300