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Loans And Allowance For Credit Losses (Summary Of Activity In The Allowance For Loan Losses) (Details) - USD ($) $ in Thousands | 12 Months Ended
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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

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- Definition Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts. + 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 (c)(4) -URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953423-111524 + Details
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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. + Details
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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 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 (c)(3) -URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953423-111524 + Details
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- Definition Amount, after recoveries, of loans and leases that have been written-off. + References No definition available. + Details
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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) -URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953423-111524 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (b)(1)(ii) -URI http://asc.fasb.org/extlink&oid=121614798&loc=d3e15032-111544 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953423-111524 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section S99 -Paragraph 4 -Subparagraph (SAB Topic 6.L.1) -URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74567-122707 + Details
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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 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953423-111524 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.11) -URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585 + Details
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