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v3.23.3

Investment Securities - Additional Information (Details) | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2023 USD ($) security instrument | Sep. 30, 2022 USD ($) | Sep. 30, 2023 USD ($) security instrument | Sep. 30, 2022 USD ($) | Dec. 31, 2022 USD ($)
Summary of Investment Holdings [Line Items] |  |  |  |  |
Transferred from available-for-sale to held-for-maturity | $ 132,300,000 |  | $ 132,300,000 |  | $ 148,900,000
Allowance for credit losses for available-for-sale debt securities | 0 |  | 0 |  | 0
Allowance for securities held-to-maturity | 150,000 |  | 150,000 |  | 150,000
Accrued interest receivable | $ 38,000,000 |  | $ 38,000,000 |  | 50,900,000
Number of securities in security portfolio | security | 3,007 |  | 3,007 |  |
Number of securities in unrealized loss position | security | 2,917 |  | 2,917 |  |
Fair Value | $ 6,414,761,000 |  | $ 6,414,761,000 |  | 6,773,712,000
Unrealized losses | 1,143,301,000 |  | 1,143,301,000 |  | 847,474,000
Equity securities, at fair value | 69,880,000 |  | 69,880,000 |  | 52,507,000
Losses on equity securities | 800,000 | $ 700,000 | 1,400,000 | $ 4,900,000 |
Impairments on equity securities without readily determinable fair value |  |  | 0 | $ 0 |
Other Assets |  |  |  |  |
Summary of Investment Holdings [Line Items] |  |  |  |  |
Equity securities without readily determinable fair value | 418,300,000 |  | 418,300,000 |  | 396,800,000
Other Assets | Partnership Interest |  |  |  |  |
Summary of Investment Holdings [Line Items] |  |  |  |  |
Equity securities without readily determinable fair value | 242,300,000 |  | 242,300,000 |  |
Other Assets | Initiatives in Low-to-Moderate Income Neighborhoods |  |  |  |  |
Summary of Investment Holdings [Line Items] |  |  |  |  |
Equity securities without readily determinable fair value | $ 176,000,000 |  | $ 176,000,000 |  |
Pooled trust preferred securities |  |  |  |  |
Summary of Investment Holdings [Line Items] |  |  |  |  |
Number of instruments held | instrument | 2 |  | 2 |  |
Fair Value | $ 11,125,000 |  | $ 11,125,000 |  | 10,811,000
Unrealized losses | $ 2,669,000 |  | $ 2,669,000 |  | $ 2,972,000

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