Loans And Leases (Impaired Loans And Leases By Class) (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	$ 366,129	$ 388,513
Total Recorded Investment	332,232	349,060
Recorded Investment No Allowance	113,447	128,058
Recorded Investment With Allowance	218,785	221,002
Related Valuation Allowance	25,301	20,451
Residential [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	157,152	158,361
Total Recorded Investment	142,435	142,871
Recorded Investment No Allowance	24,388	23,988
Recorded Investment With Allowance	118,047	118,883
Related Valuation Allowance	12,094	10,534
1-4 family [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	157,152	158,361
Total Recorded Investment	142,435	142,871
Recorded Investment No Allowance	24,388	23,988
Recorded Investment With Allowance	118,047	118,883
Related Valuation Allowance	12,094	10,534
Consumer [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	60,424	63,886
Total Recorded Investment	50,374	52,179
Recorded Investment No Allowance	26,464	27,323
Recorded Investment With Allowance	23,910	24,856
Related Valuation Allowance	4,237	4,595
Home equity [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	60,424	63,886
Total Recorded Investment	50,374	52,179
Recorded Investment No Allowance	26,464	27,323
Recorded Investment With Allowance	23,910	24,856
Related Valuation Allowance	4,237	4,595
Commercial [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	41,019	59,279
Total Recorded Investment	36,454	52,199
Recorded Investment No Allowance	16,064	23,138
Recorded Investment With Allowance	20,390	29,061
Related Valuation Allowance	2,710	1,878
Commercial non-mortgage [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	41,019	59,279
Total Recorded Investment	36,454	52,199
Recorded Investment No Allowance	16,064	23,138
Recorded Investment With Allowance	20,390	29,061
Related Valuation Allowance	2,710	1,878
Commercial real estate [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	106,905	106,738
Total Recorded Investment	102,337	101,601
Recorded Investment No Allowance	46,531	53,399
Recorded Investment With Allowance	55,806	48,202
Related Valuation Allowance	6,232	3,444
Commercial real estate [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	99,687	95,013
Total Recorded Investment	96,160	90,976
Recorded Investment No Allowance	40,575	42,774
Recorded Investment With Allowance	55,585	48,202
Related Valuation Allowance	6,222	3,444
Commercial construction [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	7,218	11,725
Total Recorded Investment	6,177	10,625
Recorded Investment No Allowance	5,956	10,625
Recorded Investment With Allowance	221	0
Related Valuation Allowance	10	0
Equipment financing [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	629	249
Total Recorded Investment	632	210
Recorded Investment No Allowance	0	210
Recorded Investment With Allowance	632	0
Related Valuation Allowance	28	0
Finance Leases Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	629	249
Total Recorded Investment	632	210
Recorded Investment No Allowance	0	210
Recorded Investment With Allowance	632	0
Related Valuation Allowance	$ 28	$ 0

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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://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 14A

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953550-111524

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- Definition

Amount of allowance for credit losses related to recorded investment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5212-111524

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (a)(4)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5212-111524

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