Loans and Leases (Summary Of Loan And Lease Portfolio Aging By Class Of Loan) (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Financing Receivable, Past Due [Line Items]
Total Loans and Leases		$ 21,641,215
90 or More Days Past Due and Accruing	$ 2,496	445
Non-accrual	109,927	167,960
Total  Past Due and Non-accrual	131,842	200,942
Consumer Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	7,091,763	6,740,680
Non-accrual	39,460	72,763
Total  Past Due and Non-accrual	48,667	92,177
Consumer Portfolio Segment [Member] | Home Equity Loan [Member]
Financing Receivable, Past Due [Line Items]
Total Loans and Leases		1,802,865
Non-accrual	23,489	31,030
Total  Past Due and Non-accrual	28,556	38,301
Consumer Portfolio Segment [Member] | Consumer Borrower [Member]
Financing Receivable, Past Due [Line Items]
Non-accrual	224	652
Total  Past Due and Non-accrual	784	2,131
Consumer Portfolio Segment [Member] | Residential Mortgage [Member]
Financing Receivable, Past Due [Line Items]
Total Loans and Leases		4,782,016
Non-accrual	15,747	41,081
Total  Past Due and Non-accrual	19,327	51,745
Commercial Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	15,179,966	14,900,535
Non-accrual	70,467	95,197
Total  Past Due and Non-accrual	83,175	108,765
Commercial Portfolio Segment [Member] | Commercial Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	6,603,180	6,322,637
Non-accrual	5,046	21,231
Total  Past Due and Non-accrual	6,490	24,250
Commercial Portfolio Segment [Member] | Non-Real Estate Receivables [Member]
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	6,882,480	7,085,076
Non-accrual	59,607	64,073
Total  Past Due and Non-accrual	69,837	66,033
Commercial Portfolio Segment [Member] | Asset Based Lending [Member]
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	1,067,248	890,598
Non-accrual	2,086	2,594
Total  Past Due and Non-accrual	2,086	3,768
Commercial Portfolio Segment [Member] | 6172 Finance Lessors [Member]
Financing Receivable, Past Due [Line Items]
Non-accrual	3,728	7,299
Total  Past Due and Non-accrual	4,762	14,714
Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	12,329	20,005
Financial Asset, 30 to 59 Days Past Due [Member] | Consumer Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	7,058	10,712
Financial Asset, 30 to 59 Days Past Due [Member] | Consumer Portfolio Segment [Member] | Home Equity Loan [Member]
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	3,467	5,500
Financial Asset, 30 to 59 Days Past Due [Member] | Consumer Portfolio Segment [Member] | Consumer Borrower [Member]
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	379	878
Financial Asset, 30 to 59 Days Past Due [Member] | Consumer Portfolio Segment [Member] | Residential Mortgage [Member]
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	3,212	4,334
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	5,271	9,293
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Commercial Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	508	2,400
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Non-Real Estate Receivables [Member]
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	3,729	612
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Asset Based Lending [Member]
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	0	1,174
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member] | 6172 Finance Lessors [Member]
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	1,034	5,107
Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	7,090	12,532
Financial Asset, 60 to 89 Days Past Due [Member] | Consumer Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	2,149	8,702
Financial Asset, 60 to 89 Days Past Due [Member] | Consumer Portfolio Segment [Member] | Home Equity Loan [Member]
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	1,600	1,771
Financial Asset, 60 to 89 Days Past Due [Member] | Consumer Portfolio Segment [Member] | Consumer Borrower [Member]
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	181	601
Financial Asset, 60 to 89 Days Past Due [Member] | Consumer Portfolio Segment [Member] | Residential Mortgage [Member]
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	368	6,330
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	4,941	3,830
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Commercial Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	417	619
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Non-Real Estate Receivables [Member]
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	4,524	903
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Asset Based Lending [Member]
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	0	0
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member] | 6172 Finance Lessors [Member]
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	0	2,308
Financial Asset, Equal to or Greater than 90 Days Past Due | Consumer Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
90 or More Days Past Due and Accruing	0	0
Financial Asset, Equal to or Greater than 90 Days Past Due | Consumer Portfolio Segment [Member] | Home Equity Loan [Member]
Financing Receivable, Past Due [Line Items]
90 or More Days Past Due and Accruing	0	0
Financial Asset, Equal to or Greater than 90 Days Past Due | Consumer Portfolio Segment [Member] | Consumer Borrower [Member]
Financing Receivable, Past Due [Line Items]
90 or More Days Past Due and Accruing	0	0
Financial Asset, Equal to or Greater than 90 Days Past Due | Consumer Portfolio Segment [Member] | Residential Mortgage [Member]
Financing Receivable, Past Due [Line Items]
90 or More Days Past Due and Accruing	0	0
Financial Asset, Equal to or Greater than 90 Days Past Due | Commercial Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
90 or More Days Past Due and Accruing	2,496	445
Financial Asset, Equal to or Greater than 90 Days Past Due | Commercial Portfolio Segment [Member] | Commercial Real Estate [Member]
Financing Receivable, Past Due [Line Items]
90 or More Days Past Due and Accruing	519	0
Financial Asset, Equal to or Greater than 90 Days Past Due | Commercial Portfolio Segment [Member] | Non-Real Estate Receivables [Member]
Financing Receivable, Past Due [Line Items]
90 or More Days Past Due and Accruing	1,977	445
Financial Asset, Equal to or Greater than 90 Days Past Due | Commercial Portfolio Segment [Member] | Asset Based Lending [Member]
Financing Receivable, Past Due [Line Items]
90 or More Days Past Due and Accruing	0	0
Financial Asset, Equal to or Greater than 90 Days Past Due | Commercial Portfolio Segment [Member] | 6172 Finance Lessors [Member]
Financing Receivable, Past Due [Line Items]
90 or More Days Past Due and Accruing	0	0
Financial Asset, Not Past Due
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	22,139,887	21,440,273
Financial Asset, Not Past Due | Consumer Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	7,043,096	6,648,503
Financial Asset, Not Past Due | Consumer Portfolio Segment [Member] | Home Equity Loan [Member]
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	1,565,003	1,764,564
Financial Asset, Not Past Due | Consumer Portfolio Segment [Member] | Consumer Borrower [Member]
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	84,515	153,668
Financial Asset, Not Past Due | Consumer Portfolio Segment [Member] | Residential Mortgage [Member]
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	5,393,578	4,730,271
Financial Asset, Not Past Due | Commercial Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	15,096,791	14,791,770
Financial Asset, Not Past Due | Commercial Portfolio Segment [Member] | Commercial Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	6,596,690	6,298,387
Financial Asset, Not Past Due | Commercial Portfolio Segment [Member] | Non-Real Estate Receivables [Member]
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	6,812,643	7,019,043
Financial Asset, Not Past Due | Commercial Portfolio Segment [Member] | Asset Based Lending [Member]
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	1,065,162	886,830
Financial Asset, Not Past Due | Commercial Portfolio Segment [Member] | 6172 Finance Lessors [Member]
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	$ 622,296	$ 587,510