Note 4 - Loans Leases Receivable - Concentration by Industries (Details) - USD ($)	Dec. 31, 2018	Dec. 31, 2017
Gross loans/leases receivable	$ 3,732,754,042	$ 2,964,485,400
Lessors of Non-residential Buildings [Member]
Gross loans/leases receivable	$ 632,534,255	$ 400,622,681
Percentage of total loans/leases	17.00%	14.00%
Lessors of Residential Buildings [Member]
Gross loans/leases receivable	$ 594,345,563	$ 370,353,561
Percentage of total loans/leases	16.00%	12.00%
Administration of Urban Planning and Community and Rural Development [Member]
Gross loans/leases receivable	$ 111,579,461	$ 83,343,541
Percentage of total loans/leases	3.00%	3.00%
Bank Holding Companies [Member]
Gross loans/leases receivable	$ 75,600,713	$ 66,950,294
Percentage of total loans/leases	2.00%	2.00%
Hotels [Member]
Gross loans/leases receivable	$ 83,105,821	$ 73,199,925
Percentage of total loans/leases	2.00%	2.00%
Nonresidential Property Managers [Member]
Gross loans/leases receivable	$ 70,211,971	$ 51,984,722
Percentage of total loans/leases	2.00%	2.00%