The percentage of assets equal to the debt instrument.

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Amount of fair value adjustment to junior subordinated debenture owed to unconsolidated subsidiary trust.

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The maximum number of consecutive quarterly periods for deferral of distributions on trust preferred securities.

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Amount of funds accepted from public in form of deposit.

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

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Amount of securities, mortgage loans, or other financial instruments pledged as collateral for deposits.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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

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Including the current and noncurrent portions, the carrying value of junior subordinated long-term debt owed to unconsolidated subsidiary trusts as of the balance sheet date. Such debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets and was initially scheduled to be repaid after one year or beyond the normal operating cycle if longer.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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The cash inflow from the additional capital contribution to the entity.

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The cash inflow from issuance of preferred stocks by a business trust or other special purpose entity, mainly established by a bank holding entity, to third party investors. The trust's assets are deeply subordinated debentures of the bank holding entity. Most trust preferred securities are subject to a mandatory redemption upon the repayment of the debentures.

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Note 11 - Long-term Borrowings (Details Textual) $ in Thousands		12 Months Ended
	Apr. 07, 2006 USD ($)	Dec. 31, 2022 USD ($)	Jun. 30, 2022 USD ($)	Dec. 31, 2021 USD ($)	Sep. 30, 2011	Jul. 01, 2011 USD ($)
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Collateral Pledged		$ 1,000,000
Federal Home Loan Bank, Advances, General Debt Obligations, Maximum Amount Available		406,700
Federal Home Loan Bank, Advances, General Debt Obligations, Amount of Available, Unused Funds		270,100
Public Deposit Accounts		220,100
Number of Consecutive Quarterly Periods for Deferral of Distributions on Trust Preferred Securities, Maximum	20
Proceeds from Issuance of Common Stock	$ 619
Junior Subordinated Debenture Owed to Unconsolidated Subsidiary Trust, Total	20,600	28,334		$ 28,232
AMNB Statutory Trust I [Member]
Equity Method Investments			$ 619
MidCarolina Trusts [Member]
Junior Subordinated Debenture Owed to Unconsolidated Subsidiary Trust, Total						$ 8,800
Equity Method Investments				264
MidCarolina Trust I [Member]
Junior Subordinated Debenture Owed to Unconsolidated Subsidiary Trust, Fair Value Adjustment		554		610		1,200
MidCarolina Trust II [Member]
Junior Subordinated Debenture Owed to Unconsolidated Subsidiary Trust, Fair Value Adjustment		495		541		$ 1,000
Private Placement [Member] \| Wholly-Owned Subsidiary, Unconsolidated [Member]
Proceeds from Issuance of Trust Preferred Securities	$ 20,000
US States and Political Subdivisions Debt Securities [Member]
Deposit Liabilities, Collateral Issued, Financial Instruments		$ 88,200
FHLB Line of Credit [Member]
Debt Instrument, Percentage of Assets		30.00%
Letters of Credit Outstanding, Amount		$ 170,000
Junior Subordinated Debt [Member] \| AMNB Statutory Trust I [Member]
Debt Instrument, Interest Rate, Effective Percentage					6.66%
Junior Subordinated Debenture Owed to Unconsolidated Subsidiary Trust, Total		$ 20,619		20,619
Junior Subordinated Debt [Member] \| AMNB Statutory Trust I [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Basis Spread on Variable Rate	1.35%	1.35%
Junior Subordinated Debt [Member] \| MidCarolina Trust I [Member]
Junior Subordinated Debenture Owed to Unconsolidated Subsidiary Trust, Total		$ 4,601		4,545
Junior Subordinated Debt [Member] \| MidCarolina Trust I [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Basis Spread on Variable Rate		3.45%
Junior Subordinated Debt [Member] \| MidCarolina Trust II [Member]
Junior Subordinated Debenture Owed to Unconsolidated Subsidiary Trust, Total		$ 3,114		$ 3,068
Junior Subordinated Debt [Member] \| MidCarolina Trust II [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Basis Spread on Variable Rate		2.95%