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v3.24.1.u1

Borrowing Arrangements Narrative (Details) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2024 USD ($) credit_line oustanding_letters_of_credit | Dec. 31, 2023 USD ($)
Line of Credit Facility [Line Items] |  |
Number of credit lines maintained by the Company | credit_line | 3 |
Federal funds purchased | $ 0 | $ 0
Letters of Credit, Federal Home Loan Bank, as collateral | $ 0 |
Maturity of repurchase agreements (less than) | 1 year 4 months 24 days |
Securities sold under repurchase agreements | $ 91,600,000 | 92,100,000
Federal Home Loan Bank borrowings, additional funding available | 2,010,000,000.00 |
Asset Pledged As Collateral, Excess Amount |  |
Line of Credit Facility [Line Items] |  |
Debt Securities | 251,900,000 | 213,100,000
Frost Bank |  |
Line of Credit Facility [Line Items] |  |
Line of credit, maximum borrowing capacity | 40,000,000 |
Line of credit, capacity available for issuance of letters of credit | $ 5,000,000 |
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 |
Amegy Bank |  |
Line of Credit Facility [Line Items] |  |
Line of credit, maximum borrowing capacity | $ 25,000,000 |
Minimum |  |
Line of Credit Facility [Line Items] |  |
Federal Home Loan Bank borrowings interest rates | 0.61% |
Federal Home Loan Bank borrowings maturities | 1 day |
Maximum |  |
Line of Credit Facility [Line Items] |  |
Federal Home Loan Bank borrowings interest rates | 4.80% |
Federal Home Loan Bank borrowings maturities | 4 years 3 months 18 days |
Federal Reserve Discount Window |  |
Line of Credit Facility [Line Items] |  |
Other borrowings | $ 250,000,000 | $ 300,000,000
Federal Reserve Bank Term Funding Program |  |
Line of Credit Facility [Line Items] |  |
Other borrowings | $ 116,100,000 |
LineOfCreditFacilityMaturity | 1 year |

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- Definition Amount, after allowance for credit loss, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), investment in debt security measured at amortized cost (held-to-maturity), and investment in debt security measured at fair value with change in fair value recognized in net income (trading). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(1)(a)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481830/320-10-45-1 + Details
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