Available lines of credit for overnight federal funds borrowings.

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Debt instrument floor rate.

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Debt instrument prepayment description.

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Debt instrument sale price to face amount percentage.

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Federal home loan bank additional borrowing capacity.

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Outstanding unfunded standby letters of credit with the FHLB.

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Fixed to floating interest rate.

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Percentage of stock, by which line of credit is secured.

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Prepayment percentage against principal amount.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Description of reference rate used for variable rate of debt instrument.

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Face (par) amount of debt instrument at time of issuance.

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Description of the frequency of periodic payments (monthly, quarterly, annual).

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Date when the debt instrument is scheduled to be fully repaid, in YYYY-MM-DD format.

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Description of the payment terms of the debt instrument (for example, whether periodic payments include principal and frequency of payments) and discussion about any contingencies associated with the payment.

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Amount of short term borrowing where a bank borrows, at the federal funds rate, from another bank.

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Amount of Federal Home Loan Bank (FHLBank) advances to member financial institutions.

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Amount of advances or credit lines available from the Federal Home Loan Bank (FHLB).

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Amount of the collateral pledged in support of federal home loan bank advances outstanding.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate.

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The cash inflow from a borrowing where a lender is placed in a lien position behind debt having a higher priority of repayment (senior) in liquidation of the entity's assets or underlying collateral.

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Date the payments are due on subordinated debt, in YYYY-MM-DD format.

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Federal Home Loan Bank and Other Borrowings - Additional Information (Details) - USD ($)	Aug. 09, 2021	Mar. 09, 2021	Dec. 31, 2023	Mar. 17, 2023	Dec. 31, 2022
Federal Home Loan Bank Advances [Line Items]
Federal home loan bank advances			$ 230,000,000,000		$ 95,000,000,000
Unfunded standby letters of credit with FHLB			75,000,000		0
Pledges under blanket floating liens			929,200,000		673,300,000
Additional borrowing capacity			210,300,000		326,800,000
Line of credit			0		0
Available lines of credit for overnight federal funds borrowings			88,500,000
Federal funds purchased			0		0
Federal Reserve Discount Window
Federal Home Loan Bank Advances [Line Items]
Federal home loan bank advances			0		25,000,000
Pledges under blanket floating liens			247,800,000		235,700,000
Available borrowing capacity under FHLB			$ 157,600,000		$ 133,100,000
Subordinated Notes
Federal Home Loan Bank Advances [Line Items]
Debt instrument, face amount		$ 40,000,000
Debt instrument, fixed interest rate		4.00%
Fixed to floating interest rate		4.00%
Debt instrument sale price to face amount percentage		100.00%
Subordinated Borrowing, Due Date		Mar. 15, 2031
Frequency of interest payment		semi-annually
Debt instrument, payment term		Interest on the Notes will accrue from March 9, 2021, and the Company will pay interest semi-annually on March 15th and September 15th of each year, beginning on September 15, 2021, until the Notes mature.
Basis spread on variable rate		3.42%
Prepayment description		The Notes may not be prepaid by the Company prior to March 15, 2026
Prepayment percentage against principal amount		100.00%
Proceeds from issuance of subordinated debt, net of loan costs		$ 19,700,000
Subordinated Notes \| SOFR
Federal Home Loan Bank Advances [Line Items]
Description of variable rate basis		three-month term Secured Overnight Financing Rate (SOFR)
ServisFirst Bank [Member]
Federal Home Loan Bank Advances [Line Items]
Line of credit agreement	$ 10,000,000			$ 20,000,000
Maturity	Mar. 17, 2024
Floor rate	3.25%
Percentage of stock, by which line of credit is secured	51.00%