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v3.24.3

Borrowing Arrangements Narrative (Details) | 9 Months Ended |
--- | --- | ---
Sep. 30, 2024 USD ($) oustanding_letters_of_credit credit_line | Dec. 31, 2023 USD ($)
Line of Credit Facility [Line Items] |  |
Number of credit lines maintained by the Company | credit_line | 3 |
Federal funds purchased | $ 0 | $ 0
Maturity of repurchase agreements (less than) | 1 year |
Securities sold under repurchase agreements | $ 80,800,000 | 92,100,000
Federal Home Loan Bank borrowings, additional funding available | 1,800,000,000 |
Asset Pledged As Collateral, Excess Amount |  |
Line of Credit Facility [Line Items] |  |
Debt Securities | 352,600,000 | 213,100,000
Frost Bank |  |
Line of Credit Facility [Line Items] |  |
Line of credit, maximum borrowing capacity | 40,000,000.0 |
Line of credit, capacity available for issuance of letters of credit | $ 5,000,000.0 |
Number of outstanding letters of credit | oustanding_letters_of_credit | 1 |
Letters of Credit Outstanding, Amount | $ 155,000 |
TIB - The Independent Bankers Bank |  |
Line of Credit Facility [Line Items] |  |
Line of credit, maximum borrowing capacity | 15,000,000.0 |
Amegy Bank |  |
Line of Credit Facility [Line Items] |  |
Line of credit, maximum borrowing capacity | $ 25,000,000.0 |
FHLB |  |
Line of Credit Facility [Line Items] |  |
Number of outstanding letters of credit | oustanding_letters_of_credit | 1 |
Letters of Credit Outstanding, Amount | $ 6,100,000 |
Minimum |  |
Line of Credit Facility [Line Items] |  |
Federal Home Loan Bank borrowings interest rates | 0.28% |
Federal Home Loan Bank borrowings maturities | 1 day |
Maximum |  |
Line of Credit Facility [Line Items] |  |
Federal Home Loan Bank borrowings interest rates | 6.65% |
Federal Home Loan Bank borrowings maturities | 3 years 9 months 18 days |
Federal Reserve Discount Window |  |
Line of Credit Facility [Line Items] |  |
Other borrowings | $ 25,000,000.0 | 300,000,000.0
Federal Reserve Bank Term Funding Program |  |
Line of Credit Facility [Line Items] |  |
Other borrowings | $ 0 | $ 117,700,000

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