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v3.25.4

Borrowed Funds - Narrative (Details) |  | 12 Months Ended
--- | --- | ---
Sep. 01, 2025 USD ($) | Dec. 31, 2025 USD ($) subordianted_debenture | Dec. 31, 2024 USD ($)
Debt Instrument [Line Items] |  |  |
Securities available-for-sale and loans pledged as collateral |  | $ 7,100,000,000 | $ 4,400,000,000
Total borrowed funds |  | 788,360,000 | 1,519,846,000
Total available borrowing capacity from FHLB |  | 3,900,000,000 |
Qualifying collateral available for FHLB borrowings |  | 7,500,000,000 |
Interest-bearing cash on hold from dealer counterparties |  | 33,100,000 | 79,600,000
Assets hold, amount |  | $ 23,220,372,000 | 11,905,326,000
Trust I |  |  |
Debt Instrument [Line Items] |  |  |
Common stock hold, percentage |  | 100.00% |
Common stock hold, value |  | $ 500,000 |
Assets hold, amount |  | $ 15,500,000 |
Trust II |  |  |
Debt Instrument [Line Items] |  |  |
Common stock hold, percentage |  | 100.00% |
Common stock hold, value |  | $ 200,000 |
Assets hold, amount |  | $ 8,200,000 |
Junior Subordinated Debt | Trust I |  |  |
Debt Instrument [Line Items] |  |  |
Variable interest rate spread (as a percent) |  | 1.85% |
Period up to which interest payments can be deferred |  | 5 years |
Junior Subordinated Debt | Trust II |  |  |
Debt Instrument [Line Items] |  |  |
Variable interest rate spread (as a percent) |  | 1.70% |
Period up to which interest payments can be deferred |  | 5 years |
FRB |  |  |
Debt Instrument [Line Items] |  |  |
Total borrowed funds |  | $ 0 | 0
Borrowing capacity |  | 601,900,000 |
FRB | Committed line of credit |  |  |
Debt Instrument [Line Items] |  |  |
Outstanding balance |  | 0 |
FRB | Uncommitted line of credit |  |  |
Debt Instrument [Line Items] |  |  |
Outstanding balance |  | 0 |
Subordinated debentures and notes |  |  |
Debt Instrument [Line Items] |  |  |
Total borrowed funds |  | $ 198,572,000 | 84,328,000
Subordinated debentures and notes | Subordinated Debenture, Due June 2033 And March 17, 2034 |  |  |
Debt Instrument [Line Items] |  |  |
Number of subordinated debentures issued by subsidiary | subordianted_debenture |  | 2 |
Subordinated debentures and notes | Subordinated debenture maturing June 26, 2033 |  |  |
Debt Instrument [Line Items] |  |  |
Principal amount |  | $ 5,000,000.0 |
Subordinated debentures and notes | Subordinated debenture maturing June 26, 2033 | Secured Overnight Financing Rate (SOFR) Spread Adjustment |  |  |
Debt Instrument [Line Items] |  |  |
Variable interest rate spread (as a percent) |  | 0.26% |
Subordinated debentures and notes | Subordinated debenture maturing June 26, 2033 | SOFR |  |  |
Debt Instrument [Line Items] |  |  |
Variable interest rate spread (as a percent) |  | 3.10% |
Subordinated debentures and notes | Subordinated debenture maturing march 17, 2034 |  |  |
Debt Instrument [Line Items] |  |  |
Principal amount |  | $ 5,000,000.0 |
Subordinated debentures and notes | Subordinated debenture maturing march 17, 2034 | Secured Overnight Financing Rate (SOFR) Spread Adjustment |  |  |
Debt Instrument [Line Items] |  |  |
Variable interest rate spread (as a percent) |  | 0.26% |
Subordinated debentures and notes | Subordinated debenture maturing march 17, 2034 | SOFR |  |  |
Debt Instrument [Line Items] |  |  |
Variable interest rate spread (as a percent) |  | 2.79% |
Subordinated debentures and notes | Subordinated debenture maturing September 15, 2029 |  |  |
Debt Instrument [Line Items] |  |  |
Total borrowed funds |  | $ 72,528,000 | 74,528,000
Principal amount |  | 75,000,000.0 |
Accretion adjustment |  | 200,000 | 200,000
Capitalized financing costs |  | $ 400,000 | $ 500,000
Subordinated debentures and notes | Subordinated debenture maturing September 15, 2029 | Secured Overnight Financing Rate (SOFR) Spread Adjustment |  |  |
Debt Instrument [Line Items] |  |  |
Variable interest rate spread (as a percent) |  | 0.26% |
Subordinated debentures and notes | Subordinated debenture maturing September 15, 2029 | SOFR |  |  |
Debt Instrument [Line Items] |  |  |
Variable interest rate spread (as a percent) |  | 3.32% |
Subordinated debentures and notes | Subordinated debenture maturing September 15, 2029 | Interest rate period 1 |  |  |
Debt Instrument [Line Items] |  |  |
Fixed interest rate |  | 6.00% |
Subordinated debentures and notes | Subordinated debenture maturing September 15, 2029 | Interest rate period 2 | Secured Overnight Financing Rate (SOFR) Spread Adjustment |  |  |
Debt Instrument [Line Items] |  |  |
Variable interest rate spread (as a percent) |  | 0.26% |
Subordinated debentures and notes | Subordinated debenture maturing September 15, 2029 | Interest rate period 2 | SOFR |  |  |
Debt Instrument [Line Items] |  |  |
Variable interest rate spread (as a percent) |  | 3.32% |
Subordinated debentures and notes | Subordinated debenture maturing June 30, 2027 |  |  |
Debt Instrument [Line Items] |  |  |
Principal amount | $ 100,000,000.0 |  |
Maturity period | 10 years |  |
Subordinated debentures and notes | Subordinated debenture maturing June 30, 2027 | Interest rate period 1 |  |  |
Debt Instrument [Line Items] |  |  |
Fixed interest rate | 5.50% |  |
Subordinated debentures and notes | Subordinated debenture maturing June 30, 2027 | Interest rate period 2 |  |  |
Debt Instrument [Line Items] |  |  |
Variable interest rate spread (as a percent) | 2.49% |  |

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