Loans And Allowance For Loan Losses (Allowance For Loan Losses And Related Loan Balance Disaggregated On The Basis Of Impairment Methodology) (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, Related Allowance	$ 2,499	$ 2,696
Impaired Financing Receivable, Recorded Investment	83,682	78,616
Loans and Leases Receivable Allowance Excluding Impaired Financing Receivable Related Allowance	158,183	157,236
Loans And Leases Receivable Excluding Impaired Financing Receivables Recorded Investment	14,378,912	14,061,682
Commercial Portfolio Segment [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, Related Allowance	1,594	1,780
Impaired Financing Receivable, Recorded Investment	66,399	61,496
Loans and Leases Receivable Allowance Excluding Impaired Financing Receivable Related Allowance	90,476	91,089
Loans And Leases Receivable Excluding Impaired Financing Receivables Recorded Investment	9,092,752	8,790,378
Personal Banking Portfolio Segment [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, Related Allowance	905	916
Impaired Financing Receivable, Recorded Investment	17,283	17,120
Loans and Leases Receivable Allowance Excluding Impaired Financing Receivable Related Allowance	67,707	66,147
Loans And Leases Receivable Excluding Impaired Financing Receivables Recorded Investment	$ 5,286,160	$ 5,271,304

Loans And Allowance For Loan Losses [Line Items]

No definition available.

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- Definition

Amount of allowance for credit losses related to the recorded investment in loans not deemed to be impaired.

+ References

No definition available.

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- Definition

Recorded investment of loan receivables, excluding impaired financing receivables.

+ References

No definition available.

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- Definition

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 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953550-111524

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- Definition

Amount of allowance for credit losses related to recorded investment.

+ 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 (a)(3)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5212-111524

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