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Amount of cash inflow from Federal Home Loan Bank (FHLBank) borrowing, classified as financing activity.

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The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

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Other Borrowings (Narrative) (Details) - USD ($)		12 Months Ended
Other Borrowings (Narrative) (Details) - USD ($)	Dec. 29, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Short-term Debt [Line Items]
Reverse repurchase agreements		$ 5,000,000
FHLBA additional credit		21,012,000
Borrowed amount from FHLBA		$ 28,187,000
Unsecured Federal Funds Outstanding Amount			$ 0	$ 0
Pettyjohn, Wood & White, Inc [Member]
Short-term Debt [Line Items]
Percentage of capital stock purchased		100.00%
National Bank of Blacksburg (NBB Note) [Member]
Short-term Debt [Line Items]
Proceeds from Issuance of Debt	$ 11,000,000
Debt Instrument, Interest Rate, Stated Percentage	4.00%
Debt instrument amortization period		15 years
Debt Instrument, Periodic Payment Terms, Balloon Payment to be Paid	$ 9,375,000
Percentage of common stock secured by first priority lien		4.95%
Community Bankers Bank [Member]
Short-term Debt [Line Items]
Unsecured federal fund lines		$ 13,000,000
Available credit		7,294,000
Zions Bank [Member]
Short-term Debt [Line Items]
Unsecured federal fund lines		4,000,000
PNC Bank [Member]
Short-term Debt [Line Items]
Unsecured federal fund lines		6,000,000
Suntrust Bank [Member]
Short-term Debt [Line Items]
Unsecured federal fund lines		10,000,000
FHLBA [Member]
Short-term Debt [Line Items]
Available credit		$ 235,788,000
Maximum [Member]
Short-term Debt [Line Items]
Period allowed to exchange securities pledged as collateral for funds		90 days
Minimum [Member]
Short-term Debt [Line Items]
Period allowed to exchange securities pledged as collateral for funds		30 days