Loans And Allowance For Credit Losses (Allowance For Loan Losses And Related Loan Balance Disaggregated On The Basis Of Impairment Methodology) (Details) $ in Thousands	Dec. 31, 2019 USD ($)
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, Related Allowance	$ 2,746
Impaired Financing Receivable, Recorded Investment	81,732
Loans and Leases Receivable Allowance Excluding Impaired Financing Receivable Related Allowance	157,936
Loans And Leases Receivable Excluding Impaired Financing Receivables Recorded Investment	14,656,085
Commercial Portfolio Segment [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, Related Allowance	1,629
Impaired Financing Receivable, Recorded Investment	64,500
Loans and Leases Receivable Allowance Excluding Impaired Financing Receivable Related Allowance	90,131
Loans And Leases Receivable Excluding Impaired Financing Receivables Recorded Investment	9,233,880
Personal Banking Portfolio Segment [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, Related Allowance	1,117
Impaired Financing Receivable, Recorded Investment	17,232
Loans and Leases Receivable Allowance Excluding Impaired Financing Receivable Related Allowance	67,805
Loans And Leases Receivable Excluding Impaired Financing Receivables Recorded Investment	$ 5,422,205

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.

+ Details

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- Definition

Recorded investment of loan receivables, excluding impaired financing receivables.

+ References

No definition available.

+ Details

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Balance Type:	debit
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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=121611835&loc=SL6953550-111524

+ Details

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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=121611835&loc=d3e5212-111524

+ Details

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