Loans and Leases (Aging Of The Outstanding Loans and Leases By Class Excluding Loans Impaired At Acquisition Date) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	$ 245,485	$ 272,770
Current	32,546,490	28,608,726
Total loans and leases	32,791,975	28,881,496
Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans and leases	22,558,060	18,836,331
Commercial | Construction and land development
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans and leases	985,424
Commercial | Commercial and industrial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans and leases	5,013,644
Commercial | Mortgage Receivable, Owner Occupied
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans and leases	11,165,012
Commercial | Mortgage Receivable, Non-Owner Occupied
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans and leases	2,987,689
Consumer Portfolio Segment
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current		9,879,384
Total loans and leases	9,771,033	10,045,165
Consumer Portfolio Segment | Construction and land development
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans and leases	348,123
Consumer Portfolio Segment | Residential Mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans and leases	5,561,686
Consumer Portfolio Segment | Revolving Mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans and leases	2,052,854
Consumer Portfolio Segment | Consumer Auto Loan
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans and leases	1,255,402
Consumer Portfolio Segment | Consumer Loan, Other
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans and leases	552,968
Non-PCI Loans | Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		74,146
Current		18,477,856
Total loans and leases		18,552,002
Non-PCI Loans | Commercial | Construction and land development
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	3,086	6,043
Current	982,338	1,007,411
Total loans and leases	985,424	1,013,454
Non-PCI Loans | Commercial | Mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		37,482
Current		12,245,153
Total loans and leases		12,282,635
Non-PCI Loans | Commercial | Other commercial real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		1,890
Current		540,138
Total loans and leases		542,028
Non-PCI Loans | Commercial | Commercial and industrial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	20,617	28,143
Current	4,993,027	4,375,649
Total loans and leases	5,013,644	4,403,792
Non-PCI Loans | Commercial | SBA-PPP
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	0
Current	2,406,291
Total loans and leases	2,406,291
Non-PCI Loans | Commercial | Other
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	67,117	588
Current	22,490,943	309,505
Total loans and leases	22,558,060	310,093
Non-PCI Loans | Commercial | Mortgage Receivable, Owner Occupied
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	25,071
Current	11,139,941
Total loans and leases	11,165,012
Non-PCI Loans | Commercial | Mortgage Receivable, Non-Owner Occupied
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	18,343
Current	2,969,346
Total loans and leases	2,987,689
Non-PCI Loans | Consumer Portfolio Segment
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	122,944	132,389
Current	9,648,089	9,638,389
Total loans and leases	9,771,033	9,770,778
Non-PCI Loans | Consumer Portfolio Segment | Construction and land development
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	1,339	2,992
Current	346,784	354,393
Total loans and leases	348,123	357,385
Non-PCI Loans | Consumer Portfolio Segment | Mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current		5,205,380
Total loans and leases		5,293,917
Non-PCI Loans | Consumer Portfolio Segment | Residential Mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	83,272	88,537
Current	5,478,414	5,205,380
Total loans and leases	5,561,686	5,293,917
Non-PCI Loans | Consumer Portfolio Segment | Revolving Mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	22,018	23,062
Current	2,030,836	2,316,010
Total loans and leases	2,052,854	2,339,072
Non-PCI Loans | Consumer Portfolio Segment | Consumer Auto Loan
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	9,736
Current	1,245,666
Total loans and leases	1,255,402
Non-PCI Loans | Consumer Portfolio Segment | Consumer Loan, Other
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	6,579
Current	546,389
Total loans and leases	552,968
Non-PCI Loans | Consumer Portfolio Segment | Consumer
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		17,798
Current		1,762,606
Total loans and leases		1,780,404
PCD Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	55,424	66,235
Current	407,458	492,481
Total loans and leases	462,882	558,716
PCD Loans | Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans and leases		284,329
PCD Loans | Consumer Portfolio Segment
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current		240,995
Total loans and leases		274,387
30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	121,499	136,220
30-59 days past due | Consumer Portfolio Segment
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		80,790
30-59 days past due | Consumer Portfolio Segment | Construction and land development
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans and leases	932
30-59 days past due | Consumer Portfolio Segment | Residential Mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans and leases	43,218
30-59 days past due | Consumer Portfolio Segment | Revolving Mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans and leases	11,977
30-59 days past due | Consumer Portfolio Segment | Consumer Auto Loan
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans and leases	6,825
30-59 days past due | Consumer Portfolio Segment | Consumer Loan, Other
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans and leases	3,610
30-59 days past due | Non-PCI Loans | Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		42,716
30-59 days past due | Non-PCI Loans | Commercial | Construction and land development
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	956	3,146
30-59 days past due | Non-PCI Loans | Commercial | Mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		20,389
30-59 days past due | Non-PCI Loans | Commercial | Other commercial real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		861
30-59 days past due | Non-PCI Loans | Commercial | Commercial and industrial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	14,532	18,269
30-59 days past due | Non-PCI Loans | Commercial | SBA-PPP
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	0
30-59 days past due | Non-PCI Loans | Commercial | Other
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	36,615	51
30-59 days past due | Non-PCI Loans | Commercial | Mortgage Receivable, Owner Occupied
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	8,757
30-59 days past due | Non-PCI Loans | Commercial | Mortgage Receivable, Non-Owner Occupied
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	12,370
30-59 days past due | Non-PCI Loans | Consumer Portfolio Segment
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	66,562	67,026
30-59 days past due | Non-PCI Loans | Consumer Portfolio Segment | Construction and land development
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	932	977
30-59 days past due | Non-PCI Loans | Consumer Portfolio Segment | Mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		45,839
30-59 days past due | Non-PCI Loans | Consumer Portfolio Segment | Residential Mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	43,218	45,839
30-59 days past due | Non-PCI Loans | Consumer Portfolio Segment | Revolving Mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	11,977	9,729
30-59 days past due | Non-PCI Loans | Consumer Portfolio Segment | Consumer Auto Loan
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	6,825
30-59 days past due | Non-PCI Loans | Consumer Portfolio Segment | Consumer Loan, Other
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	3,610
30-59 days past due | Non-PCI Loans | Consumer Portfolio Segment | Consumer
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		10,481
30-59 days past due | PCD Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	18,322	26,478
Total loans and leases	18,322
30-59 days past due | PCD Loans | Consumer Portfolio Segment
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		13,764
60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	26,043	51,058
60-89 days past due | Consumer Portfolio Segment
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		31,329
60-89 days past due | Consumer Portfolio Segment | Construction and land development
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans and leases	77
60-89 days past due | Consumer Portfolio Segment | Residential Mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans and leases	8,364
60-89 days past due | Consumer Portfolio Segment | Revolving Mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans and leases	2,626
60-89 days past due | Consumer Portfolio Segment | Consumer Auto Loan
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans and leases	1,835
60-89 days past due | Consumer Portfolio Segment | Consumer Loan, Other
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans and leases	1,464
60-89 days past due | Non-PCI Loans | Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		14,553
60-89 days past due | Non-PCI Loans | Commercial | Construction and land development
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	527	195
60-89 days past due | Non-PCI Loans | Commercial | Mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		8,774
60-89 days past due | Non-PCI Loans | Commercial | Other commercial real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		331
60-89 days past due | Non-PCI Loans | Commercial | Commercial and industrial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	2,842	4,842
60-89 days past due | Non-PCI Loans | Commercial | SBA-PPP
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	0
60-89 days past due | Non-PCI Loans | Commercial | Other
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	5,601	411
60-89 days past due | Non-PCI Loans | Commercial | Mortgage Receivable, Owner Occupied
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	2,232
60-89 days past due | Non-PCI Loans | Commercial | Mortgage Receivable, Non-Owner Occupied
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	0
60-89 days past due | Non-PCI Loans | Consumer Portfolio Segment
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	14,366	25,721
60-89 days past due | Non-PCI Loans | Consumer Portfolio Segment | Construction and land development
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	77	218
60-89 days past due | Non-PCI Loans | Consumer Portfolio Segment | Mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		18,289
60-89 days past due | Non-PCI Loans | Consumer Portfolio Segment | Residential Mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	8,364	18,289
60-89 days past due | Non-PCI Loans | Consumer Portfolio Segment | Revolving Mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	2,626	3,468
60-89 days past due | Non-PCI Loans | Consumer Portfolio Segment | Consumer Auto Loan
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	1,835
60-89 days past due | Non-PCI Loans | Consumer Portfolio Segment | Consumer Loan, Other
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	1,464
60-89 days past due | Non-PCI Loans | Consumer Portfolio Segment | Consumer
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		3,746
60-89 days past due | PCD Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	6,076	10,784
Total loans and leases	6,076
60-89 days past due | PCD Loans | Consumer Portfolio Segment
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		5,608
90 days or greater
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	97,943	85,492
90 days or greater | Consumer Portfolio Segment
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		53,662
90 days or greater | Consumer Portfolio Segment | Construction and land development
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans and leases	330
90 days or greater | Consumer Portfolio Segment | Residential Mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans and leases	31,690
90 days or greater | Consumer Portfolio Segment | Revolving Mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans and leases	7,415
90 days or greater | Consumer Portfolio Segment | Consumer Auto Loan
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans and leases	1,076
90 days or greater | Consumer Portfolio Segment | Consumer Loan, Other
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans and leases	1,505
90 days or greater | Non-PCI Loans | Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		16,877
90 days or greater | Non-PCI Loans | Commercial | Construction and land development
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	1,603	2,702
90 days or greater | Non-PCI Loans | Commercial | Mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		8,319
90 days or greater | Non-PCI Loans | Commercial | Other commercial real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		698
90 days or greater | Non-PCI Loans | Commercial | Commercial and industrial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	3,243	5,032
90 days or greater | Non-PCI Loans | Commercial | SBA-PPP
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	0
90 days or greater | Non-PCI Loans | Commercial | Other
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	24,901	126
90 days or greater | Non-PCI Loans | Commercial | Mortgage Receivable, Owner Occupied
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	14,082
90 days or greater | Non-PCI Loans | Commercial | Mortgage Receivable, Non-Owner Occupied
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	5,973
90 days or greater | Non-PCI Loans | Consumer Portfolio Segment
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	42,016	39,642
90 days or greater | Non-PCI Loans | Consumer Portfolio Segment | Construction and land development
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	330	1,797
90 days or greater | Non-PCI Loans | Consumer Portfolio Segment | Mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		24,409
90 days or greater | Non-PCI Loans | Consumer Portfolio Segment | Residential Mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	31,690	24,409
90 days or greater | Non-PCI Loans | Consumer Portfolio Segment | Revolving Mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	7,415	9,865
90 days or greater | Non-PCI Loans | Consumer Portfolio Segment | Consumer Auto Loan
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	1,076
90 days or greater | Non-PCI Loans | Consumer Portfolio Segment | Consumer Loan, Other
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	1,505
90 days or greater | Non-PCI Loans | Consumer Portfolio Segment | Consumer
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		3,571
90 days or greater | PCD Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	31,026	28,973
Total loans and leases	$ 31,026
90 days or greater | PCD Loans | Consumer Portfolio Segment
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		$ 14,020