Loans and Leases (Interest Income From Impaired Loans And Leases, By Class) (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	$ 263,812	$ 252,843	$ 256,289	$ 251,978
Accrued Interest Income	2,104	2,182	4,274	4,128
Cash Basis Interest Income	523	515	1,067	1,018
Residential Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	101,245	110,787	101,850	111,965
Accrued Interest Income	912	948	1,820	1,929
Cash Basis Interest Income	282	265	546	518
Consumer Portfolio Segment [Member] \| Home Equity Loan [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	38,092	42,112	38,238	43,536
Accrued Interest Income	287	290	556	584
Cash Basis Interest Income	241	250	521	500
Commercial Portfolio Segment [Member] \| Commercial and Industrial Sector [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	106,753	80,475	98,511	78,896
Accrued Interest Income	844	871	1,764	1,410
Cash Basis Interest Income	0	0	0	0
Commercial Portfolio Segment [Member] \| Asset Based Loans [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	201	1,347	204	875
Accrued Interest Income	0	0	0	0
Cash Basis Interest Income	0	0	0	0
Commercial Real Estate Portfolio Segment [Member] \| Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	13,070	11,802	12,354	11,951
Accrued Interest Income	61	38	134	134
Cash Basis Interest Income	0	0	0	0
Finance Leases Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	4,451	6,320	5,132	4,755
Accrued Interest Income	0	35	0	71
Cash Basis Interest Income	$ 0	$ 0	$ 0	$ 0

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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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