Note 8 - Loans Receivable, Net - Credit Quality Indicators (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Current year	$ 94,424,768		$ 94,424,768
One year before	154,610,074		154,610,074
Two years before	103,308,393		103,308,393
Three years before	46,729,960		46,729,960
Four years before	41,163,055		41,163,055
Prior	108,967,307		108,967,307
Revolving	60,579,708		60,579,708
Loans	609,783,265		609,783,265		$ 560,987,903
Total loans gross write-offs	53,513	$ 54,192	143,071	$ 97,884
Pass [Member]
Loans					439,247,847
Caution [Member]
Loans					105,368,984
Special Mention [Member]
Loans					7,123,873
Substandard [Member]
Loans					9,247,199
Commercial Real Estate Portfolio Segment [Member] | Construction Loans [Member]
Current year	22,386,450		22,386,450
One year before	41,427,376		41,427,376
Two years before	18,933,471		18,933,471
Three years before	8,055,869		8,055,869
Four years before	3,225,826		3,225,826
Prior	2,436,955		2,436,955
Revolving	5,027,869		5,027,869
Loans	101,493,816		101,493,816		112,793,694
Current year, writen off			0
One year before gross write-offs			0
Two years before gross write-offs			1,270
Three years before gross write-offs			0
Four years before gross write-offs			0
Prior gross write-offs			0
Revolving gross write-offs			0
Total loans gross write-offs	(0)	(0)	1,270	(0)
Commercial Real Estate Portfolio Segment [Member] | Construction Loans [Member] | Pass [Member]
Current year	19,418,021		19,418,021
One year before	26,601,678		26,601,678
Two years before	16,516,378		16,516,378
Three years before	4,725,200		4,725,200
Four years before	648,158		648,158
Prior	1,465,033		1,465,033
Revolving	5,027,869		5,027,869
Loans	74,402,337		74,402,337		91,564,058
Commercial Real Estate Portfolio Segment [Member] | Construction Loans [Member] | Caution [Member]
Current year	2,968,429		2,968,429
One year before	14,796,433		14,796,433
Two years before	2,083,717		2,083,717
Three years before	3,193,709		3,193,709
Four years before	418,495		418,495
Prior	416,565		416,565
Revolving	0		0
Loans	23,877,348		23,877,348		18,837,894
Commercial Real Estate Portfolio Segment [Member] | Construction Loans [Member] | Special Mention [Member]
Current year	0		0
One year before	29,265		29,265
Two years before	0		0
Three years before	0		0
Four years before	921,594		921,594
Prior	458,064		458,064
Revolving	0		0
Loans	1,408,923		1,408,923		2,013,824
Commercial Real Estate Portfolio Segment [Member] | Construction Loans [Member] | Substandard [Member]
Current year	0		0
One year before	0		0
Two years before	333,376		333,376
Three years before	136,960		136,960
Four years before	1,237,579		1,237,579
Prior	97,293		97,293
Revolving	0		0
Loans	1,805,208		1,805,208		377,918
Commercial Real Estate Portfolio Segment [Member] | Residential Mortgage [Member]
Current year	35,734,329		35,734,329
One year before	44,151,728		44,151,728
Two years before	17,866,585		17,866,585
Three years before	16,731,052		16,731,052
Four years before	5,762,286		5,762,286
Prior	30,158,406		30,158,406
Revolving	9,576,457		9,576,457
Loans	159,980,843		159,980,843		110,056,973
Current year, writen off			0
One year before gross write-offs			0
Two years before gross write-offs			0
Three years before gross write-offs			0
Four years before gross write-offs			0
Prior gross write-offs			0
Revolving gross write-offs			0
Total loans gross write-offs	(0)	(0)	0	(0)
Commercial Real Estate Portfolio Segment [Member] | Residential Mortgage [Member] | Pass [Member]
Current year	23,244,544		23,244,544
One year before	32,870,741		32,870,741
Two years before	10,942,223		10,942,223
Three years before	14,632,321		14,632,321
Four years before	4,096,019		4,096,019
Prior	23,193,947		23,193,947
Revolving	9,576,457		9,576,457
Loans	118,556,252		118,556,252		84,028,037
Commercial Real Estate Portfolio Segment [Member] | Residential Mortgage [Member] | Caution [Member]
Current year	10,537,035		10,537,035
One year before	11,122,672		11,122,672
Two years before	5,868,656		5,868,656
Three years before	1,699,406		1,699,406
Four years before	1,617,666		1,617,666
Prior	4,237,468		4,237,468
Revolving	0		0
Loans	35,082,903		35,082,903		22,372,649
Commercial Real Estate Portfolio Segment [Member] | Residential Mortgage [Member] | Special Mention [Member]
Current year	1,878,200		1,878,200
One year before	158,315		158,315
Two years before	434,467		434,467
Three years before	399,325		399,325
Four years before	0		0
Prior	245,555		245,555
Revolving	0		0
Loans	3,115,862		3,115,862		887,874
Commercial Real Estate Portfolio Segment [Member] | Residential Mortgage [Member] | Substandard [Member]
Current year	74,550		74,550
One year before	0		0
Two years before	621,239		621,239
Three years before	0		0
Four years before	48,601		48,601
Prior	2,481,436		2,481,436
Revolving	0		0
Loans	3,225,826		3,225,826		2,768,413
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate [Member]
Current year	21,016,505		21,016,505
One year before	54,563,732		54,563,732
Two years before	53,627,220		53,627,220
Three years before	19,699,212		19,699,212
Four years before	31,328,117		31,328,117
Prior	73,153,723		73,153,723
Revolving	2,787,316		2,787,316
Loans	256,175,825		256,175,825		252,154,475
Current year, writen off			0
One year before gross write-offs			0
Two years before gross write-offs			0
Three years before gross write-offs			0
Four years before gross write-offs			0
Prior gross write-offs			0
Revolving gross write-offs			0
Total loans gross write-offs	(0)	(0)	0	(0)
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate [Member] | Pass [Member]
Current year	11,017,973		11,017,973
One year before	48,666,315		48,666,315
Two years before	48,839,955		48,839,955
Three years before	12,796,698		12,796,698
Four years before	24,093,992		24,093,992
Prior	54,378,489		54,378,489
Revolving	2,687,505		2,687,505
Loans	202,480,927		202,480,927		196,063,300
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate [Member] | Caution [Member]
Current year	9,786,032		9,786,032
One year before	4,949,460		4,949,460
Two years before	4,272,692		4,272,692
Three years before	6,488,251		6,488,251
Four years before	7,234,125		7,234,125
Prior	8,389,414		8,389,414
Revolving	0		0
Loans	41,119,974		41,119,974		47,821,422
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate [Member] | Special Mention [Member]
Current year	212,500		212,500
One year before	879,781		879,781
Two years before	455,971		455,971
Three years before	414,263		414,263
Four years before	0		0
Prior	5,784,828		5,784,828
Revolving	99,811		99,811
Loans	7,847,154		7,847,154		3,270,916
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate [Member] | Substandard [Member]
Current year	0		0
One year before	68,176		68,176
Two years before	58,602		58,602
Three years before	0		0
Four years before	0		0
Prior	4,600,992		4,600,992
Revolving	0		0
Loans	4,727,770		4,727,770		4,998,837
Commercial and Agricultural Loans [Member]
Current year	7,695,159		7,695,159
One year before	7,752,554		7,752,554
Two years before	9,927,678		9,927,678
Three years before	793,587		793,587
Four years before	408,963		408,963
Prior	2,936,752		2,936,752
Revolving	4,890,296		4,890,296
Loans	34,404,989		34,404,989		30,647,975
Current year, writen off			0
One year before gross write-offs			0
Two years before gross write-offs			15,880
Three years before gross write-offs			0
Four years before gross write-offs			0
Prior gross write-offs			0
Revolving gross write-offs			0
Total loans gross write-offs	(0)	(0)	15,880	(0)
Commercial and Agricultural Loans [Member] | Pass [Member]
Current year	3,819,756		3,819,756
One year before	6,182,554		6,182,554
Two years before	8,078,460		8,078,460
Three years before	692,988		692,988
Four years before	379,558		379,558
Prior	2,558,790		2,558,790
Revolving	4,153,369		4,153,369
Loans	25,865,475		25,865,475		25,383,994
Commercial and Agricultural Loans [Member] | Caution [Member]
Current year	3,416,339		3,416,339
One year before	1,529,379		1,529,379
Two years before	1,732,343		1,732,343
Three years before	82,772		82,772
Four years before	18,316		18,316
Prior	217,590		217,590
Revolving	639,351		639,351
Loans	7,636,090		7,636,090		4,593,283
Commercial and Agricultural Loans [Member] | Special Mention [Member]
Current year	459,064		459,064
One year before	40,621		40,621
Two years before	116,875		116,875
Three years before	15,852		15,852
Four years before	11,089		11,089
Prior	95,193		95,193
Revolving	0		0
Loans	738,694		738,694		371,071
Commercial and Agricultural Loans [Member] | Substandard [Member]
Current year	0		0
One year before	0		0
Two years before	0		0
Three years before	1,975		1,975
Four years before	0		0
Prior	65,179		65,179
Revolving	97,576		97,576
Loans	164,730		164,730		299,627
Consumer Portfolio Segment [Member] | Home Equity Line of Credit [Member]
Current year	0		0
One year before	0		0
Two years before	0		0
Three years before	0		0
Four years before	0		0
Prior	0		0
Revolving	33,318,762		33,318,762
Loans	33,318,762		33,318,762		31,736,676
Current year, writen off			0
One year before gross write-offs			0
Two years before gross write-offs			0
Three years before gross write-offs			0
Four years before gross write-offs			0
Prior gross write-offs			0
Revolving gross write-offs			1,488
Total loans gross write-offs	(0)	(0)	1,488	(0)
Consumer Portfolio Segment [Member] | Home Equity Line of Credit [Member] | Pass [Member]
Current year	0		0
One year before	0		0
Two years before	0		0
Three years before	0		0
Four years before	0		0
Prior	0		0
Revolving	27,331,177		27,331,177
Loans	27,331,177		27,331,177		25,693,252
Consumer Portfolio Segment [Member] | Home Equity Line of Credit [Member] | Caution [Member]
Current year	0		0
One year before	0		0
Two years before	0		0
Three years before	0		0
Four years before	0		0
Prior	0		0
Revolving	4,964,475		4,964,475
Loans	4,964,475		4,964,475		5,018,419
Consumer Portfolio Segment [Member] | Home Equity Line of Credit [Member] | Special Mention [Member]
Current year	0		0
One year before	0		0
Two years before	0		0
Three years before	0		0
Four years before	0		0
Prior	0		0
Revolving	401,065		401,065
Loans	401,065		401,065		401,550
Consumer Portfolio Segment [Member] | Home Equity Line of Credit [Member] | Substandard [Member]
Current year	0		0
One year before	0		0
Two years before	0		0
Three years before	0		0
Four years before	0		0
Prior	0		0
Revolving	622,045		622,045
Loans	622,045		622,045		623,455
Consumer Portfolio Segment [Member] | Other Consumer Loans [Member]
Current year	7,592,325		7,592,325
One year before	6,714,684		6,714,684
Two years before	2,953,439		2,953,439
Three years before	1,450,240		1,450,240
Four years before	437,863		437,863
Prior	281,471		281,471
Revolving	4,979,008		4,979,008
Loans	24,409,030		24,409,030		23,598,110
Current year, writen off			0
One year before gross write-offs			20,456
Two years before gross write-offs			13,970
Three years before gross write-offs			17,036
Four years before gross write-offs			0
Prior gross write-offs			0
Revolving gross write-offs			72,971
Total loans gross write-offs	53,513	$ 54,192	124,433	$ 97,884
Consumer Portfolio Segment [Member] | Other Consumer Loans [Member] | Pass [Member]
Current year	5,493,794		5,493,794
One year before	4,261,711		4,261,711
Two years before	1,849,151		1,849,151
Three years before	859,558		859,558
Four years before	238,942		238,942
Prior	211,390		211,390
Revolving	4,683,874		4,683,874
Loans	17,598,420		17,598,420		16,515,206
Consumer Portfolio Segment [Member] | Other Consumer Loans [Member] | Caution [Member]
Current year	2,059,332		2,059,332
One year before	2,262,793		2,262,793
Two years before	1,024,964		1,024,964
Three years before	547,223		547,223
Four years before	181,936		181,936
Prior	60,196		60,196
Revolving	282,634		282,634
Loans	6,419,078		6,419,078		6,725,317
Consumer Portfolio Segment [Member] | Other Consumer Loans [Member] | Special Mention [Member]
Current year	39,199		39,199
One year before	129,630		129,630
Two years before	0		0
Three years before	0		0
Four years before	0		0
Prior	0		0
Revolving	6,285		6,285
Loans	175,114		175,114		178,638
Consumer Portfolio Segment [Member] | Other Consumer Loans [Member] | Substandard [Member]
Current year	0		0
One year before	60,550		60,550
Two years before	79,324		79,324
Three years before	43,459		43,459
Four years before	16,985		16,985
Prior	9,885		9,885
Revolving	6,215		6,215
Loans	$ 216,418		$ 216,418		$ 178,949