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

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

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Including both current and noncurrent portions, Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer.

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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 cash inflow from the additional capital contribution to the entity.

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Stated interest rate of the subordinated debt.

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Note 11 - Long-term Borrowings (Details Textual)			12 Months Ended	21 Months Ended
Note 11 - Long-term Borrowings (Details Textual)	Sep. 30, 2011	Apr. 07, 2006 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 30, 2020	Apr. 01, 2019 USD ($)	Jul. 01, 2011 USD ($)
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Collateral Pledged			$ 1,051,176,000
Long-term Federal Home Loan Bank Advances, Total				$ 0
Public Deposit Accounts			326,595,000
Subordinated Debt, Ending Balance			0	7,500,000
Proceeds from Issuance of Long-term Debt, Total		$ 20,000,000
Number of Consecutive Quarterly Periods for Deferral of Distributions on Trust Preferred Securities, Maximum		20
Proceeds from Issuance of Common Stock		$ 619,000
Junior Subordinated Debenture Owed to Unconsolidated Subsidiary Trust, Total		$ 20,619,000
MidCarolina Trusts [Member]
Junior Subordinated Debenture Owed to Unconsolidated Subsidiary Trust, Total							$ 8,764,000
Equity Method Investments			264,000
AMNB Statutory Trust I [Member]
Equity Method Investments			619,000
MidCarolina Trust I [Member]
Junior Subordinated Debenture Owed to Unconsolidated Subsidiary Trust, Fair Value Adjustment			610,000	666,000			1,197,000
MidCarolina Trust II [Member]
Junior Subordinated Debenture Owed to Unconsolidated Subsidiary Trust, Fair Value Adjustment			541,000	587,000			$ 1,021,000
HomeTown Bankshares Corporation [Member]
Subordinated Debt, Ending Balance						$ 7,500,000
US States and Political Subdivisions Debt Securities [Member]
Deposit Liabilities, Collateral Issued, Financial Instruments			$ 96,495,000
FHLB Line of Credit [Member]
Debt Instrument, Percentage of Assets			30.00%
Letters of Credit Outstanding, Amount			$ 275,000,000
Subordinated Debt [Member]
Subordinated Borrowing, Interest Rate					6.75%
Subordinated Debt [Member] \| HomeTown Bankshares Corporation [Member]
Liabilities, Fair Value Adjustment				30,000
Junior Subordinated Debt [Member]
Subordinated Borrowing, Interest Rate		6.66%
Junior Subordinated Debenture Owed to Unconsolidated Subsidiary Trust, Total			28,232,000	28,130,000
Junior Subordinated Debt [Member] \| AMNB Statutory Trust I [Member]
Junior Subordinated Debenture Owed to Unconsolidated Subsidiary Trust, Total			20,619,000	20,619,000
Junior Subordinated Debt [Member] \| MidCarolina Trust I [Member]
Junior Subordinated Debenture Owed to Unconsolidated Subsidiary Trust, Total			4,545,000	4,489,000
Junior Subordinated Debt [Member] \| MidCarolina Trust II [Member]
Junior Subordinated Debenture Owed to Unconsolidated Subsidiary Trust, Total			$ 3,068,000	$ 3,022,000
Junior Subordinated Debt [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Basis Spread on Variable Rate	1.35%
Junior Subordinated Debt [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| AMNB Statutory Trust I [Member]
Debt Instrument, Basis Spread on Variable Rate			1.35%
Junior Subordinated Debt [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| MidCarolina Trust I [Member]
Debt Instrument, Basis Spread on Variable Rate			3.45%
Junior Subordinated Debt [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| MidCarolina Trust II [Member]
Debt Instrument, Basis Spread on Variable Rate			2.95%