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Loans And Allowance For Credit Losses (Summary of Activity in the Allowance For Credit Losses) (Details) - USD ($) $ in Thousands | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2020 | Jan. 01, 2020 | Dec. 31, 2019
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financing Receivable, Allowance for Credit Loss | $ 220,834 | $ 139,643 |
Financing Receivable, Credit Loss, Expense (Reversal) | 116,049 |  |
Financing Receivable, Allowance for Credit Loss, Writeoff | 50,047 |  |
Financing Receivable, Allowance for Credit Loss, Recovery | 15,189 |  |
Financing Receivable, Allowance for Credit Loss, Writeoff, after Recovery | 34,858 |  |
Off-Balance Sheet, Credit Loss, Liability | 38,307 | 17,165 | $ 1,075
Off-Balance Sheet, Credit Loss, Liability, Credit Loss Expense (Reversal) | 21,142 |  |
Financing Receivable, Allowance for Credit Loss and Unfunded Lending Commitments, Total | 259,141 |  |
Previously Reported [Member] |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financing Receivable, Allowance for Credit Loss |  |  | 160,682
Off-Balance Sheet, Credit Loss, Liability |  |  | 1,075
Revision of Prior Period, Adjustment [Member] |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financing Receivable, Allowance for Credit Loss |  | (21,039) |
Off-Balance Sheet, Credit Loss, Liability |  | 16,090 |
Commercial Portfolio Segment [Member] |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financing Receivable, Allowance for Credit Loss | 121,549 | 62,049 |
Financing Receivable, Credit Loss, Expense (Reversal) | 63,115 |  |
Financing Receivable, Allowance for Credit Loss, Writeoff | 7,862 |  |
Financing Receivable, Allowance for Credit Loss, Recovery | 4,247 |  |
Financing Receivable, Allowance for Credit Loss, Writeoff, after Recovery | 3,615 |  |
Off-Balance Sheet, Credit Loss, Liability | 37,259 | 16,456 |
Off-Balance Sheet, Credit Loss, Liability, Credit Loss Expense (Reversal) | 20,803 |  |
Financing Receivable, Allowance for Credit Loss and Unfunded Lending Commitments, Total | 158,808 |  |
Commercial Portfolio Segment [Member] | Previously Reported [Member] |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financing Receivable, Allowance for Credit Loss |  |  | 91,760
Off-Balance Sheet, Credit Loss, Liability |  |  | 399
Commercial Portfolio Segment [Member] | Revision of Prior Period, Adjustment [Member] |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financing Receivable, Allowance for Credit Loss |  | (29,711) |
Off-Balance Sheet, Credit Loss, Liability |  | 16,057 |
Personal Banking Portfolio Segment [Member] |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financing Receivable, Allowance for Credit Loss | 99,285 | 77,594 |
Financing Receivable, Credit Loss, Expense (Reversal) | 52,934 |  |
Financing Receivable, Allowance for Credit Loss, Writeoff | 42,185 |  |
Financing Receivable, Allowance for Credit Loss, Recovery | 10,942 |  |
Financing Receivable, Allowance for Credit Loss, Writeoff, after Recovery | 31,243 |  |
Off-Balance Sheet, Credit Loss, Liability | 1,048 | 709 |
Off-Balance Sheet, Credit Loss, Liability, Credit Loss Expense (Reversal) | 339 |  |
Financing Receivable, Allowance for Credit Loss and Unfunded Lending Commitments, Total | $ 100,333 |  |
Personal Banking Portfolio Segment [Member] | Previously Reported [Member] |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financing Receivable, Allowance for Credit Loss |  |  | 68,922
Off-Balance Sheet, Credit Loss, Liability |  |  | $ 676
Personal Banking Portfolio Segment [Member] | Revision of Prior Period, Adjustment [Member] |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financing Receivable, Allowance for Credit Loss |  | 8,672 |
Off-Balance Sheet, Credit Loss, Liability |  | $ 33 |

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