Note 3 - Loans Leases Receivable - Leases By Delinquency Status (Details) - USD ($)		Mar. 31, 2018		Dec. 31, 2017
Loans		$ 3,046,799,276		$ 2,956,713,493
Commercial Portfolio Segment [Member]
Loans	[1]	1,201,085,625		1,134,516,315
Finance Leases Portfolio Segment [Member]
Loans	[1],[2]	137,614,465		141,448,232
Residential Portfolio Segment [Member]
Loans	[3]	254,484,231	[2]	258,646,265
Consumer Portfolio Segment [Member]
Loans	[2]	95,911,569		118,610,799
Commercial, Lease, Residential, and Consumer Portfolio Segments [Member]
Loans	[2]	$ 566,922,056		$ 585,463,694
As a % of Total	[2]	100.00%		100.00%
Performing Financial Instruments [Member] | Commercial Portfolio Segment [Member]
Loans	[2]	$ 77,987,539		$ 65,847,177
Performing Financial Instruments [Member] | Finance Leases Portfolio Segment [Member]
Loans	[2]	134,638,869		137,778,740
Performing Financial Instruments [Member] | Residential Portfolio Segment [Member]
Loans	[2]	253,025,270		256,935,448
Performing Financial Instruments [Member] | Consumer Portfolio Segment [Member]
Loans	[2]	95,626,776		118,333,529
Performing Financial Instruments [Member] | Commercial, Lease, Residential, and Consumer Portfolio Segments [Member]
Loans	[2]	$ 561,278,454		$ 578,894,894
As a % of Total	[2]	99.00%		98.88%
Nonperforming Financial Instruments [Member]
Loans		$ 18,075,417		$ 18,642,377
Nonperforming Financial Instruments [Member] | Commercial Portfolio Segment [Member]
Loans		6,199,154		6,455,535
Nonperforming Financial Instruments [Member] | Finance Leases Portfolio Segment [Member]
Loans	[2]	2,975,596		3,669,492
Nonperforming Financial Instruments [Member] | Residential Portfolio Segment [Member]
Loans	[2]	1,458,961		1,710,818
Nonperforming Financial Instruments [Member] | Consumer Portfolio Segment [Member]
Loans	[2]	284,793		277,270
Nonperforming Financial Instruments [Member] | Commercial, Lease, Residential, and Consumer Portfolio Segments [Member]
Loans	[2]	$ 5,643,602		$ 6,568,800
As a % of Total	[2]	1.00%		1.12%

[1] Includes equipment financing agreements outstanding at m2, totaling $78,911,791 and $66,758,397 as of March 31, 2018 and December 31, 2017, respectively.

[2] Performing = loans/leases accruing and less than 90 days past due. Nonperforming = loans/leases on nonaccrual, accruing loans/leases that are greater than or equal to 90 days past due, and accruing TDRs.

[3] Includes residential real estate loans held for sale totaling $279,750 and $645,001 as of March 31, 2018, and December 31, 2017, respectively.