Note 2 - Acquisitions - Surrey Acquisition (Details) - USD ($) $ / shares in Units, $ in Thousands		Apr. 21, 2023	Sep. 30, 2024	Dec. 31, 2023	[1]
Noninterest-bearing			$ 869,723	$ 931,920
Interest-bearing			1,789,530	1,790,405
Total deposits			2,659,253	2,722,325
Goodwill			$ 143,946	$ 143,946
Surrey [Member]
Cash and cash equivalents		$ 176,700
Securities-available-for-sale	[2]	20,934
Loans held for investment, net of allowance and mark	[3]	239,080
Premises and equipment	[4]	6,275
Other assets	[5],[6]	10,558
Intangible assets	[7]	12,700
Total assets		466,247
Noninterest-bearing		158,389
Interest-bearing	[8]	245,246
Total deposits		403,635
Long term debt		0
Other liabilities	[9]	5,623
Total liabilities		409,258
Net identifiable assets acquired over liabilities assumed		56,989
Goodwill		14,381
Net assets acquired over liabilities assumed		$ 71,370
First Community Bankshares, Inc. common stock issued (in shares)		2,996,786
Purchase price per share of the Company's common stock (in dollars per share)		$ 23.81
Fair value of Company common stock issued		$ 71,354
Cash paid for fractional shares		16
Fair Value of total consideration transferred		71,370
Surrey [Member] | Recorded By Surrey [Member]
Cash and cash equivalents		176,700
Securities-available-for-sale	[2]	22,027
Loans held for investment, net of allowance and mark	[3]	251,944
Premises and equipment	[4]	5,501
Other assets	[5],[6]	10,787
Intangible assets	[7]	0
Total assets		466,959
Noninterest-bearing		158,389
Interest-bearing	[8]	246,460
Total deposits		404,849
Long term debt		0
Other liabilities	[9]	6,004
Total liabilities		410,853
Net identifiable assets acquired over liabilities assumed		56,106
Goodwill		0
Net assets acquired over liabilities assumed		56,106
Surrey [Member] | Fair Value Adjustments [Member]
Cash and cash equivalents		0
Securities-available-for-sale	[2]	(1,093)
Loans held for investment, net of allowance and mark	[3]	(12,864)
Premises and equipment	[4]	774
Other assets	[5],[6]	(229)
Intangible assets	[7]	12,700
Total assets		(712)
Noninterest-bearing		0
Interest-bearing	[8]	(1,214)
Total deposits		(1,214)
Long term debt		0
Other liabilities	[9]	(381)
Total liabilities		(1,595)
Net identifiable assets acquired over liabilities assumed		883
Goodwill		14,381
Net assets acquired over liabilities assumed		$ 15,264

[1] Derived from audited financial statements

[2] Adjustment reflects the fair value adjustment based on the Company's evaluation of the acquired investment portfolio.

[3] Adjustment reflects the fair value adjustments of $(15.80) million based on the Company's evaluation of the acquired loan portfolio and excludes the allowance for credit losses and deferred loans fees of $2.94 million as recorded by Surrey.

[4] Adjustment reflects the fair value adjustments based on the Company's evaluation of the acquired premises and equipment.

[5] Adjustment reflects the fair value adjustment based on the Company's evaluation of stocks with other banks of $47 thousand.

[6] Adjustment to record the deferred tax asset related to the fair value adjustments $(177) thousand.

[7] Adjustment to record the core deposit intangible on the acquired deposit accounts.

[8] Adjustment reflects the fair value adjustment based on the Company's evaluation of the time deposit portfolio.

[9] Adjustment to reclass deferred tax asset $(99) thousand, goodwill $(282) thousand, federal income tax payable $(389) thousand, and state income tax payable $8 thousand.