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Loans And Allowance For Loan Losses - Narrative (Details) | 12 Months Ended |
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Dec. 31, 2022 USD ($) contract | Dec. 31, 2021 USD ($) contract | Dec. 31, 2020 USD ($) contract | Dec. 31, 2019 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Loans and leases receivable, impaired, interest lost on nonaccrual loans | $ 9,000,000 | $ 12,000,000 |  |
Cash-basis interest income recognized | 3,000,000 | 2,400,000 |  |
Financing receivable, change in method, credit loss expense (reversal) |  |  | $ 18,300,000 |
Transfers to held for sale |  |  | 1,430,000,000 |
Financing receivable, allowance for credit loss | 443,424,000 | 427,597,000 | 605,736,000 | $ 281,402,000
Reserve for unfunded commitments | 57,500,000 |  |  |
All financing receivable, allowance for credit loss | 500,900,000 | 469,500,000 |  |
Provision for (reversal of) loan losses | $ 31,400,000 |  |  |
ACL to loans ratio | 1.15% |  |  |
Decrease in ACL to loans ratio | 0.0004 |  |  |
Allowance for credit loss, reasonable and supportable forecast period | 2 years |  |  |
Allowance for credit loss, straight-line basis historical period | 1 year |  |  |
Modifications, post-modification recorded investment | $ 131,186,000 | 48,932,000 | $ 76,615,000 |
Commitments to lend additional funds to TDRs |  | $ 0 |  |
Troubled Debt Restructuring That Subsequently Defaulted |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Subsequent default, number of contracts | contract | 5,000 | 8 | 7 |
Modifications, post-modification recorded investment | $ 1,000,000 | $ 978,000 | $ 21,700,000 |
Baseline |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Estimated unemployment rate | 4.70% | 4.40% |  |
Unfunded Loan Commitment |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Financing receivable, allowance for credit loss |  | $ 41,900,000 |  |
Substandard |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Retail loan substandard period (in days) | 90 days |  |  |
Loss And Charged Off |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Retail loan charge off (in days) | 120 days |  |  |
Commercial And Industrial |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Modifications, post-modification recorded investment | $ 105,610,000 | 27,618,000 | $ 28,917,000 |
Commercial And Industrial | Small Business Administration (SBA), CARES Act, Paycheck Protection Program |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Loans | 14,700,000 | 399,600,000 |  |
Asset Pledged as Collateral |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Loans | $ 16,090,000,000.00 | $ 14,190,000,000 |  |

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