Loans And Allowance For Credit Losses (Summary Of Activity In The Allowance For Loan Losses) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Allowance for Loan and Lease Losses [Roll Forward]
Balance at start of period	$ 159,932	$ 159,532
Provision	50,438	42,694
Loans charged off	61,880	55,821
Less recoveries on loans	12,192	13,527
Allowance for Loan and Lease Losses Write-Offs; Net, Total	49,688	42,294
Balance at end of period	160,682	159,932
Commercial Portfolio Segment [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Balance at start of period	92,869	93,704
Provision	2,816	254
Loans charged off	4,711	3,164
Less recoveries on loans	786	2,075
Allowance for Loan and Lease Losses Write-Offs; Net, Total	3,925	1,089
Balance at end of period	91,760	92,869
Personal Banking Portfolio Segment [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Balance at start of period	67,063	65,828
Provision	47,622	42,440
Loans charged off	57,169	52,657
Less recoveries on loans	11,406	11,452
Allowance for Loan and Lease Losses Write-Offs; Net, Total	45,763	41,205
Balance at end of period	$ 68,922	$ 67,063

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

+ References

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- Definition

Amount, after recoveries, of loans and leases that have been written-off.

+ References

No definition available.

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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
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- Definition

Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
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-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585

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