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Loans and Leases - Narrative (Details) - USD ($) $ in Millions |  | 3 Months Ended | 9 Months Ended |
--- | --- | --- | --- | ---
Mar. 27, 2023 | Sep. 30, 2023 | Sep. 30, 2023 | Dec. 31, 2022
Receivables [Abstract] |  |  |  |
Financing receivable, accrued interest receivable |  | $ 620.0 | $ 620.0 | $ 203.0
Financing receivable, amortization of purchase discount |  | $ 275.0 | $ 535.0 |
Financing receivable, threshold period past due |  | 30 days | 30 days |
Other real estate owned |  | $ 62.0 | $ 62.0 | 47.0
Financing receivable, troubled debt restructuring, commitment to lend |  | $ 25.0 | 25.0 | $ 1.5
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Modified loans that subsequently defaulted |  |  | 21.0 |
Innovation C&I and cash flow dependent |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Modified loans that subsequently defaulted |  |  | 15.0 |
Investor dependent - early stage |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Modified loans that subsequently defaulted |  |  | $ 3.0 |
SVB | FDIC Credit Facility |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Debt instrument, term | 5 years |  |  |
FDIC advances, maximum amount available | $ 70,000.0 |  |  |

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