Loans and Leases (Impaired Collateral) (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	$ 309,422	$ 256,410
Commercial Portfolio Segment [Member] | Non-Real Estate Receivables [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	119,884	102,254
Commercial Portfolio Segment [Member] | Asset Based Loans [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	2,594	139
Commercial Portfolio Segment [Member] | Commercial Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	33,879	23,297
Commercial Portfolio Segment [Member] | Equipment Loan [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	7,298	5,433
Commercial Portfolio Segment [Member] | Residential Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment		90,096
Consumer Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment		256,410
Consumer Portfolio Segment [Member] | Residential Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	98,164	90,096
Consumer Portfolio Segment [Member] | Home Equity Loan [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	46,950	35,191
Consumer Portfolio Segment [Member] | Consumer Loan [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	653	0
Collateral Pledged [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	102,836	59,550
Collateral Pledged [Member] | Commercial Portfolio Segment [Member] | Non-Real Estate Receivables [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	11,074	10,682
Collateral Pledged [Member] | Commercial Portfolio Segment [Member] | Asset Based Loans [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	2,504	0
Collateral Pledged [Member] | Commercial Portfolio Segment [Member] | Commercial Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	28,482	14,097
Collateral Pledged [Member] | Commercial Portfolio Segment [Member] | Equipment Loan [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	0	0
Collateral Pledged [Member] | Consumer Portfolio Segment [Member] | Residential Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	33,980	17,635
Collateral Pledged [Member] | Consumer Portfolio Segment [Member] | Home Equity Loan [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	26,796	17,136
Collateral Pledged [Member] | Consumer Portfolio Segment [Member] | Consumer Loan [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	0	0
Uncollateralized [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	206,586	196,860
Uncollateralized [Member] | Commercial Portfolio Segment [Member] | Non-Real Estate Receivables [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	108,810	91,572
Uncollateralized [Member] | Commercial Portfolio Segment [Member] | Asset Based Loans [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	90	139
Uncollateralized [Member] | Commercial Portfolio Segment [Member] | Commercial Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	5,397	9,200
Uncollateralized [Member] | Commercial Portfolio Segment [Member] | Equipment Loan [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	7,298	5,433
Uncollateralized [Member] | Consumer Portfolio Segment [Member] | Residential Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	64,184	72,461
Uncollateralized [Member] | Consumer Portfolio Segment [Member] | Home Equity Loan [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	20,154	18,055
Uncollateralized [Member] | Consumer Portfolio Segment [Member] | Consumer Loan [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	653	0
Collateral Value [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	$ 150,300	$ 109,800