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	Jun. 30, 2019	Dec. 31, 2018
Loans And Allowance For Loan Losses [Line Items]
Loans And Leases Receivable Excluding Impaired Financing Receivables Recorded Investment	$ 14,203,738	$ 14,061,682
Impaired Financing Receivable, Recorded Investment	56,510	78,616
Loans and Leases Receivable Allowance Excluding Impaired Financing Receivable Related Allowance	159,279	157,236
Impaired Financing Receivable, Related Allowance	1,903	2,696
Commercial Portfolio Segment [Member]
Loans And Allowance For Loan Losses [Line Items]
Loans And Leases Receivable Excluding Impaired Financing Receivables Recorded Investment	8,996,421	8,790,378
Impaired Financing Receivable, Recorded Investment	38,876	61,496
Loans and Leases Receivable Allowance Excluding Impaired Financing Receivable Related Allowance	90,902	91,089
Impaired Financing Receivable, Related Allowance	906	1,780
Personal Banking Portfolio Segment [Member]
Loans And Allowance For Loan Losses [Line Items]
Loans And Leases Receivable Excluding Impaired Financing Receivables Recorded Investment	5,207,317	5,271,304
Impaired Financing Receivable, Recorded Investment	17,634	17,120
Loans and Leases Receivable Allowance Excluding Impaired Financing Receivable Related Allowance	68,377	66,147
Impaired Financing Receivable, Related Allowance	$ 997	$ 916

Loans And Allowance For Loan Losses [Line Items]

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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=84173941&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=84173941&loc=d3e5212-111524

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