Premises and Equipment and Leases Premises and Equipment and Leases (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Premises and Equipment [Line Items]
Premises and equipment	$ 1,094,202	$ 974,568
Less accumulated depreciation	471,979	409,393
Premises and equipment, net of accumulated depreciation	622,223	565,175
Depreciation Expense	68,700	68,400	$ 63,400
Lessee, Operating Lease, Liability, Payment, Due [Abstract]
Operating Leases, Payments Due, 2024	34,000
Operating Leases, Payments, 2025	33,351
Operating Leases, Payments, 2026	32,844
Operating Leases, Payments, 2027	30,416
Operating Lease, Payments, 2028	28,930
Operating Leases, Payments, 2029 and later	182,273
Total undiscounted lease payments	341,814
Less: Interest	85,512
Lease liabilities	$ 256,302
Operating Lease, Liability, Statement of Financial Position [Extensible Enumeration]	Other liabilities
Lease, Cost [Abstract]
Operating Lease, Right-of-Use Asset	$ 221,000	$ 177,000
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Premises and equipment, net of accumulated depreciation	Premises and equipment, net of accumulated depreciation
Operating Lease, Weighted Average Remaining Lease Term	9 years 4 months 24 days
Operating Lease, Weighted Average Discount Rate, Percent	3.10%
Lease, Cost	$ 42,200	$ 41,700	35,800
Operating Lease, costs recognized as occupancy and equipment expense	25,300	24,500	23,400
Operating Lease, operating cash flows	26,800	23,300	25,300
Short-term Lease, Cost	15,600	13,000	$ 11,500
Land
Premises and Equipment [Line Items]
Premises and equipment	69,121	69,944
Buildings and improvements
Premises and Equipment [Line Items]
Premises and equipment	525,941	469,001
Software and related integration
Premises and Equipment [Line Items]
Premises and equipment	219,646	198,057
Furniture and equipment
Premises and Equipment [Line Items]
Premises and equipment	211,082	201,830
Construction in progress
Premises and Equipment [Line Items]
Premises and equipment	$ 68,412	$ 35,736