Note 3 - Loans Leases Receivable - Impaired Loans Leases (Details) - USD ($)	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Recorded investment with no specific allowance recorded	$ 9,536,052	$ 4,926,710	$ 7,117,268
Unpaid principal balance with no specific allowance recorded	9,625,107	5,011,928	7,202,484
Average recorded investment with no specific allowance recorded	10,182,919	5,121,057
Interest income recognized with no specific allowance recorded	87,519	27,408
Interest income recognized for cash payments received with no specific allowance recorded	87,519	27,408
Recorded investment with specific allowance recorded	8,270,598	15,273,374	11,236,897
Unpaid principal balance with specific allowance recorded	8,293,674	15,277,213	11,240,836
Related allowance	3,227,366	3,748,557	3,043,319
Average recorded investment with specific allowance recorded	7,747,299	14,810,049
Interest income recognized with specific allowance recorded	5,000	67,018
Interest income recognized for cash payments received with specific allowance recorded	5,000	67,018
Recorded investment	17,806,650	20,200,084	18,354,163
Unpaid principal balance	17,918,781	20,289,141	18,443,318
Average recorded investment	17,930,218	19,931,106
Interest income recognized	92,519	94,426
Interest income recognized for cash payments received	92,519	94,426
Commercial Portfolio Segment [Member]
Recorded investment with no specific allowance recorded	5,038,888	835,955	1,634,269
Unpaid principal balance with no specific allowance recorded	5,053,164	846,392	1,644,706
Average recorded investment with no specific allowance recorded	5,297,775	927,387
Interest income recognized with no specific allowance recorded	75,406	7,352
Interest income recognized for cash payments received with no specific allowance recorded	75,406	7,352
Recorded investment with specific allowance recorded	957,524	8,352,499	4,613,940
Unpaid principal balance with specific allowance recorded	957,524	8,356,338	4,617,879
Related allowance	567,321	1,751,774	715,627
Average recorded investment with specific allowance recorded	824,536	8,110,658
Interest income recognized with specific allowance recorded	1,983	62,666
Interest income recognized for cash payments received with specific allowance recorded	1,983	62,666
Recorded investment	5,996,412	9,188,454	6,248,209
Unpaid principal balance	6,010,688	9,202,730	6,262,585
Average recorded investment	6,122,311	9,038,045
Interest income recognized	77,389	70,018
Interest income recognized for cash payments received	77,389	70,018
Commercial Real Estate Portfolio Segment [Member] | Owner Occupied Commercial Real Estate Loans [Member]
Recorded investment with no specific allowance recorded	289,261		289,261
Unpaid principal balance with no specific allowance recorded	289,261		289,261
Average recorded investment with no specific allowance recorded	289,261
Interest income recognized with no specific allowance recorded	5,822
Interest income recognized for cash payments received with no specific allowance recorded	5,822
Recorded investment with specific allowance recorded	147,375	322,148	151,962
Unpaid principal balance with specific allowance recorded	147,375	322,148	151,962
Related allowance	43,875	57,398	48,462
Average recorded investment with specific allowance recorded	149,669	322,148
Interest income recognized with specific allowance recorded
Interest income recognized for cash payments received with specific allowance recorded
Recorded investment	436,636	322,148	441,222
Unpaid principal balance	436,636	322,148	441,222
Average recorded investment	438,930	322,148
Interest income recognized	5,822
Interest income recognized for cash payments received	5,822
Commercial Real Estate Portfolio Segment [Member] | Construction Loans [Member]
Recorded investment with no specific allowance recorded
Unpaid principal balance with no specific allowance recorded
Average recorded investment with no specific allowance recorded
Interest income recognized with no specific allowance recorded
Interest income recognized for cash payments received with no specific allowance recorded
Recorded investment with specific allowance recorded	5,430,268	4,349,267	4,844,312
Unpaid principal balance with specific allowance recorded	5,430,268	4,349,267	4,844,312
Related allowance	1,627,022	823,061	1,379,235
Average recorded investment with specific allowance recorded	5,137,290	4,351,542
Interest income recognized with specific allowance recorded
Interest income recognized for cash payments received with specific allowance recorded
Recorded investment	5,430,268	4,349,267	4,844,312
Unpaid principal balance	5,430,268	4,349,267	4,844,312
Average recorded investment	5,137,290	4,351,542
Interest income recognized
Interest income recognized for cash payments received
Commercial Real Estate Portfolio Segment [Member] | Other Non-owner Occupied Commercial Real Estate Loans [Member]
Recorded investment with no specific allowance recorded	1,227,579	1,174,260	1,171,565
Unpaid principal balance with no specific allowance recorded	1,227,579	1,174,260	1,171,565
Average recorded investment with no specific allowance recorded	1,235,654	1,183,813
Interest income recognized with no specific allowance recorded
Interest income recognized for cash payments received with no specific allowance recorded
Recorded investment with specific allowance recorded		78,386	72,163
Unpaid principal balance with specific allowance recorded		78,386	72,163
Related allowance		7,986	1,763
Average recorded investment with specific allowance recorded		39,193
Interest income recognized with specific allowance recorded
Interest income recognized for cash payments received with specific allowance recorded
Recorded investment	1,227,579	1,252,646	1,243,728
Unpaid principal balance	1,227,579	1,252,646	1,243,728
Average recorded investment	1,235,654	1,223,006
Interest income recognized
Interest income recognized for cash payments received
Finance Leases Portfolio Segment [Member]
Recorded investment with no specific allowance recorded	1,927,663	1,593,104	2,944,540
Unpaid principal balance with no specific allowance recorded	1,927,663	1,593,104	2,944,540
Average recorded investment with no specific allowance recorded	2,355,745	1,868,355
Interest income recognized with no specific allowance recorded	6,291	18,895
Interest income recognized for cash payments received with no specific allowance recorded	6,291	18,895
Recorded investment with specific allowance recorded	1,047,933	1,488,964	724,953
Unpaid principal balance with specific allowance recorded	1,047,933	1,488,964	724,953
Related allowance	628,379	795,840	504,469
Average recorded investment with specific allowance recorded	962,961	1,300,811
Interest income recognized with specific allowance recorded
Interest income recognized for cash payments received with specific allowance recorded
Recorded investment	2,975,596	3,082,068	3,669,492
Unpaid principal balance	2,975,596	3,082,068	3,669,492
Average recorded investment	3,318,706	3,169,166
Interest income recognized	6,291	18,895
Interest income recognized for cash payments received	6,291	18,895
Residential Portfolio Segment [Member]
Recorded investment with no specific allowance recorded	911,804	1,147,434	943,388
Unpaid principal balance with no specific allowance recorded	986,583	1,222,215	1,018,167
Average recorded investment with no specific allowance recorded	884,441	1,025,656
Interest income recognized with no specific allowance recorded		1,161
Interest income recognized for cash payments received with no specific allowance recorded		1,161
Recorded investment with specific allowance recorded	547,158	633,340	761,458
Unpaid principal balance with specific allowance recorded	570,234	633,340	761,458
Related allowance	248,592	274,566	355,167
Average recorded investment with specific allowance recorded	544,558	636,134
Interest income recognized with specific allowance recorded	2,934	4,240
Interest income recognized for cash payments received with specific allowance recorded	2,934	4,240
Recorded investment	1,458,962	1,780,774	1,704,846
Unpaid principal balance	1,556,817	1,855,555	1,779,625
Average recorded investment	1,428,999	1,661,790
Interest income recognized	2,934	5,401
Interest income recognized for cash payments received	2,934	5,401
Consumer Portfolio Segment [Member]
Recorded investment with no specific allowance recorded	140,857	175,957	134,245
Unpaid principal balance with no specific allowance recorded	140,857	175,957	134,245
Average recorded investment with no specific allowance recorded	120,043	115,846
Interest income recognized with no specific allowance recorded
Interest income recognized for cash payments received with no specific allowance recorded
Recorded investment with specific allowance recorded	140,340	48,770	68,109
Unpaid principal balance with specific allowance recorded	140,340	48,770	68,109
Related allowance	112,177	37,932	38,596
Average recorded investment with specific allowance recorded	128,285	49,563
Interest income recognized with specific allowance recorded	83	112
Interest income recognized for cash payments received with specific allowance recorded	83	112
Recorded investment	281,197	224,727	202,354
Unpaid principal balance	281,197	224,727	$ 202,354
Average recorded investment	248,328	165,409
Interest income recognized	83	112
Interest income recognized for cash payments received	$ 83	$ 112