Loans and Allowance for Credit Losses (Aging Analysis of Past Due Loans by Portfolio Class) (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	$ 23,921,917	$ 23,114,046
Recorded Investment > 90 Days and Accruing	9,609	4,585
30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	70,766	65,080
60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	22,881	38,779
Greater Than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	50,034	28,372
Total Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	143,681	132,231
Current [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	23,778,236	22,981,815
Total Commercial [Member] | Commercial Real Estate - Income Producing [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	3,986,943	3,560,991
Total Commercial [Member] | Construction and Land Development [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	1,551,091	1,703,592
Recorded Investment > 90 Days and Accruing	742	54
Total Commercial [Member] | 30-59 Days Past Due [Member] | Commercial Real Estate - Income Producing [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	3,938	879
Total Commercial [Member] | 30-59 Days Past Due [Member] | Construction and Land Development [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	1,655	4,029
Total Commercial [Member] | 60-89 Days Past Due [Member] | Commercial Real Estate - Income Producing [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	606
Total Commercial [Member] | 60-89 Days Past Due [Member] | Construction and Land Development [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	1,220	242
Total Commercial [Member] | Greater Than 90 Days Past Due [Member] | Commercial Real Estate - Income Producing [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	408	1,174
Total Commercial [Member] | Greater Than 90 Days Past Due [Member] | Construction and Land Development [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	1,208	133
Total Commercial [Member] | Total Past Due [Member] | Commercial Real Estate - Income Producing [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	4,952	2,053
Total Commercial [Member] | Total Past Due [Member] | Construction and Land Development [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	4,083	4,404
Total Commercial [Member] | Current [Member] | Commercial Real Estate - Income Producing [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	3,981,991	3,558,938
Total Commercial [Member] | Current [Member] | Construction and Land Development [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	1,547,008	1,699,188
Total Commercial [Member] | Total Commercial And Industrial [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	13,051,047	13,179,511
Recorded Investment > 90 Days and Accruing	6,213	2,619
Total Commercial [Member] | Total Commercial And Industrial [Member] | Commercial Non-Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	9,957,284	10,146,453
Recorded Investment > 90 Days and Accruing	5,782	996
Total Commercial [Member] | Total Commercial And Industrial [Member] | Commercial Real Estate - Owner Occupied [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	3,093,763	3,033,058
Recorded Investment > 90 Days and Accruing	431	1,623
Total Commercial [Member] | Total Commercial And Industrial [Member] | 30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	13,925	23,119
Total Commercial [Member] | Total Commercial And Industrial [Member] | 30-59 Days Past Due [Member] | Commercial Non-Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	12,311	4,050
Total Commercial [Member] | Total Commercial And Industrial [Member] | 30-59 Days Past Due [Member] | Commercial Real Estate - Owner Occupied [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	1,614	19,069
Total Commercial [Member] | Total Commercial And Industrial [Member] | 60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	5,977	24,675
Total Commercial [Member] | Total Commercial And Industrial [Member] | 60-89 Days Past Due [Member] | Commercial Non-Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	4,381	21,329
Total Commercial [Member] | Total Commercial And Industrial [Member] | 60-89 Days Past Due [Member] | Commercial Real Estate - Owner Occupied [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	1,596	3,346
Total Commercial [Member] | Total Commercial And Industrial [Member] | Greater Than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	22,847	5,312
Total Commercial [Member] | Total Commercial And Industrial [Member] | Greater Than 90 Days Past Due [Member] | Commercial Non-Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	21,132	3,418
Total Commercial [Member] | Total Commercial And Industrial [Member] | Greater Than 90 Days Past Due [Member] | Commercial Real Estate - Owner Occupied [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	1,715	1,894
Total Commercial [Member] | Total Commercial And Industrial [Member] | Total Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	42,749	53,106
Total Commercial [Member] | Total Commercial And Industrial [Member] | Total Past Due [Member] | Commercial Non-Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	37,824	28,797
Total Commercial [Member] | Total Commercial And Industrial [Member] | Total Past Due [Member] | Commercial Real Estate - Owner Occupied [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	4,925	24,309
Total Commercial [Member] | Total Commercial And Industrial [Member] | Current [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	13,008,298	13,126,405
Total Commercial [Member] | Total Commercial And Industrial [Member] | Current [Member] | Commercial Non-Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	9,919,460	10,117,656
Total Commercial [Member] | Total Commercial And Industrial [Member] | Current [Member] | Commercial Real Estate - Owner Occupied [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	3,088,838	3,008,749
Residential Mortgages [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	3,886,072	3,092,605
Recorded Investment > 90 Days and Accruing	172	293
Residential Mortgages [Member] | 30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	40,189	28,208
Residential Mortgages [Member] | 60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	9,121	11,056
Residential Mortgages [Member] | Greater Than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	18,960	17,346
Residential Mortgages [Member] | Total Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	68,270	56,610
Residential Mortgages [Member] | Current [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	3,817,802	3,035,995
Consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	1,446,764	1,577,347
Recorded Investment > 90 Days and Accruing	2,482	1,619
Consumer [Member] | 30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	11,059	8,845
Consumer [Member] | 60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	5,957	2,806
Consumer [Member] | Greater Than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	6,611	4,407
Consumer [Member] | Total Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	23,627	16,058
Consumer [Member] | Current [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	$ 1,423,137	$ 1,561,289