Loans and Leases (Interest Income From Impaired Loans And Leases, By Class) (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	$ 261,939	$ 261,612	$ 264,982	$ 256,386
Accrued Interest Income	1,920	2,133	6,194	6,261
Cash Basis Interest Income	517	539	1,584	1,557
Commercial Portfolio Segment [Member] \| Commercial and Industrial Sector [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	102,996	94,618	103,772	87,603
Accrued Interest Income	751	847	2,515	2,257
Commercial Portfolio Segment [Member] \| Asset Based Loans [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	4,673	1,095	4,694	809
Accrued Interest Income	0	0	0	0
Commercial Real Estate Portfolio Segment [Member] \| Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	13,567	11,222	12,042	10,497
Accrued Interest Income	60	30	194	164
Commercial Real Estate Portfolio Segment [Member] \| Construction Loans [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	1,484	0	1,484	0
Accrued Interest Income			0	0
Finance Leases Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	4,718	6,337	5,901	4,907
Accrued Interest Income	0	41	0	112
Residential Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	97,917	107,618	99,599	109,948
Accrued Interest Income	862	923	2,682	2,852
Cash Basis Interest Income	271	301	817	819
Consumer Portfolio Segment [Member] \| Home Equity Loan [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	36,584	40,722	37,490	42,622
Accrued Interest Income	247	292	803	876
Cash Basis Interest Income	$ 246	$ 238	$ 767	$ 738

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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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