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v3.25.4

Borrowings - FHLB Advances - Additional Information (Details) | 12 Months Ended
--- | ---
Dec. 31, 2025 USD ($) Loan | Dec. 31, 2024 USD ($) Loan | Dec. 31, 2023 USD ($)
Debt Instrument [Line Items] |  |  |
Weighted-average cost related to FHLB advances (in hundredths) | 3.64% | 4.60% |
Weighted average remaining maturity | 2 days | 8 days |
Dallas [Member] | Federal Home Loan Bank Advances |  |  |
Debt Instrument [Line Items] |  |  |
Number of outstanding short-term FHLB advances | Loan | 2 | 2 |
Short-term FHLB advances | $ 225,000,000 | $ 200,000,000 |
Interest expense, long-term borrowings | 0 | 0 | $ 0
Long-term FHLB advances | 0 | 0 |
Additional debt instrument borrowing capacity | 1,962,000,000 | 4,292,000,000 |
Dallas [Member] | Short Term FhlbAdvances1 [Member] | Federal Home Loan Bank Advances |  |  |
Debt Instrument [Line Items] |  |  |
Short-term FHLB advances | $ 150,000,000 |  |
Interest rate (in hundredths) | 3.62% |  |
Dallas [Member] | Short Term FhlbAdvances2 [Member] | Federal Home Loan Bank Advances |  |  |
Debt Instrument [Line Items] |  |  |
Short-term FHLB advances | $ 75,000,000 |  |
Interest rate (in hundredths) | 3.67% |  |
Dallas [Member] | Fair Market Value Adjustment [Member] | Federal Home Loan Bank Advances |  |  |
Debt Instrument [Line Items] |  |  |
Interest expense, short-term borrowings | $ 9,500,000 | $ 16,800,000 | $ 49,900,000

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