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v3.25.3

BORROWINGS - Additional Information (Details) $ in Millions | 1 Months Ended | 3 Months Ended | 9 Months Ended |
--- | --- | --- | --- | ---
Oct. 31, 2025 USD ($) | Sep. 30, 2025 USD ($) trust | Jun. 30, 2025 USD ($) | Sep. 30, 2025 USD ($) trust | Dec. 31, 2024 USD ($)
Debt Instrument [Line Items] |  |  |  |  |
Short-term advances |  | $ 0.0 |  | $ 0.0 | $ 0.0
Federal home loan bank, advances, interest rate |  | 0.35% |  | 0.35% | 0.34%
Aggregate principal amount |  | $ 745.0 |  | $ 745.0 |
Number of unconsolidated subsidiary trusts | trust |  | 4 |  | 4 |
Trust Preferred Securities |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Basis points, interest rate, type [Extensible Enumeration] |  |  |  | Secured Overnight Financing Rate (SOFR) [Member] |
Tenor spread adjustment |  |  |  | 0.0026 |
FHLB |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Credit available with FHLB |  | $ 12,600.0 |  | $ 12,600.0 |
FHLB amount available for borrowing |  | 9,700.0 |  | 9,700.0 |
Collateral pledged |  | 17,600.0 |  | 17,600.0 |
Other Subordinated Debt |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt matured or redeemed |  |  | $ 25.0 |  |
Aggregate principal amount |  | 245.0 |  | 245.0 |
Other Subordinated Debt | Subsequent Event |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt matured or redeemed | $ 100.0 |  |  |  |
Other Subordinated Debt | 4.875% Subordinated Notes due 2025 |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Aggregate principal amount |  | 100.0 |  | 100.0 |
Senior Notes |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt matured or redeemed |  | 350.0 |  |  |
Aggregate principal amount |  | 500.0 |  | 500.0 |
Other Wholesale Credit |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Remaining borrowing capacity |  | $ 7,100.0 |  | $ 7,100.0 |
Maximum | FHLB |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Effective interest rates |  | 4.69% |  | 4.69% | 4.88%
Minimum | FHLB |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Effective interest rates |  | 3.69% |  | 3.69% | 3.69%
FHLB |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Short-term advances |  | $ 415.0 |  | $ 415.0 | $ 335.0
Short-term advances, overnight maturities, percentage |  | 48.00% |  | 48.00% | 57.30%
Basis points, interest rate, type [Extensible Enumeration] |  |  |  | Secured Overnight Financing Rate (SOFR) [Member] |
Other Subordinated Debt | Maximum |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt term |  |  |  | 1 year |

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