Loans and Leases (Interest Income From Impaired Loans And Leases, By Class) (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	$ 294,260	$ 266,853
Accrued Interest Income	2,437	2,170
Cash Basis Interest Income	1,460	544
Commercial Portfolio Segment [Member] \| Commercial and Industrial Sector [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	122,835	107,529
Accrued Interest Income	1,053	920
Commercial Portfolio Segment [Member] \| Asset Based Lending
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	138	222
Accrued Interest Income	0	0
Commercial Portfolio Segment [Member] \| Commercial Real Estate
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	23,903	11,544
Accrued Interest Income	146	73
Commercial Portfolio Segment [Member] \| 6172 Finance Lessors
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	7,192	5,634
Accrued Interest Income	0	0
Consumer Portfolio Segment [Member] \| Residential Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	97,778	102,926
Accrued Interest Income	830	908
Cash Basis Interest Income	630	264
Consumer Portfolio Segment [Member] \| Home Equity Loan [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	41,902	38,998
Accrued Interest Income	391	269
Cash Basis Interest Income	830	280
Consumer Portfolio Segment [Member] \| Consumer Loan
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	512	0
Accrued Interest Income	17	0
Cash Basis Interest Income	$ 0	$ 0

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- Definition

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5212-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5258-111524

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Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

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