Note 4 - Loans Leases Receivable - Loans Leases Nonperforming Loans Leases (Details) - USD ($)	Sep. 30, 2018	Dec. 31, 2017
Accruing Past Due 90 Days or More	$ 1,409,355	$ 88,671
Nonaccrual Loans/Leases	23,576,285	11,441,234
Accruing TDRs	7,276,337	9,394,967
Loans and Leases Receivable, Net of Deferred Income	$ 3,644,099,503	$ 2,956,713,493
Percentage of Total NPLs	100.00%	100.00%
Nonperforming Financial Instruments [Member]
Accruing Past Due 90 Days or More	$ 1,409,355	$ 88,671
Nonaccrual Loans/Leases	23,576,285	11,441,234
Accruing TDRs	4,239,915	7,112,472
Loans and Leases Receivable, Net of Deferred Income	$ 29,225,555	$ 18,642,377
Percentage of Total NPLs	100.00%	100.00%
Commercial Portfolio Segment [Member]
Nonaccrual Loans/Leases	$ 8,046,588	$ 1,231,353
Loans and Leases Receivable, Net of Deferred Income	1,380,542,524	1,134,516,315
Commercial Portfolio Segment [Member] \| Nonperforming Financial Instruments [Member]
Nonaccrual Loans/Leases	8,046,588	1,231,353
Accruing TDRs	677,859	5,224,182
Loans and Leases Receivable, Net of Deferred Income	$ 8,724,447	$ 6,455,535
Percentage of Total NPLs	29.85%	34.63%
Commercial Real Estate Portfolio Segment [Member]
Loans and Leases Receivable, Net of Deferred Income	$ 1,727,326,190	$ 1,303,491,882
Commercial Real Estate Portfolio Segment [Member] \| Owner Occupied Commercial Real Estate Loans [Member]
Nonaccrual Loans/Leases	408,648	333,900
Loans and Leases Receivable, Net of Deferred Income	449,056,125	332,742,477
Commercial Real Estate Portfolio Segment [Member] \| Construction Loans [Member]
Accruing Past Due 90 Days or More	1,131,975
Nonaccrual Loans/Leases	1,655,809	4,844,312
Loans and Leases Receivable, Net of Deferred Income	224,295,259	186,402,404
Commercial Real Estate Portfolio Segment [Member] \| Other Non-owner Occupied Commercial Real Estate Loans [Member]
Nonaccrual Loans/Leases	10,293,961	1,243,728
Loans and Leases Receivable, Net of Deferred Income	1,053,974,806	784,347,000
Commercial Real Estate Portfolio Segment [Member] \| Nonperforming Financial Instruments [Member] \| Owner Occupied Commercial Real Estate Loans [Member]
Nonaccrual Loans/Leases	408,648	333,900
Accruing TDRs	106,470	107,322
Loans and Leases Receivable, Net of Deferred Income	$ 515,118	$ 441,222
Percentage of Total NPLs	1.76%	2.37%
Commercial Real Estate Portfolio Segment [Member] \| Nonperforming Financial Instruments [Member] \| Construction Loans [Member]
Accruing Past Due 90 Days or More	$ 1,131,975
Nonaccrual Loans/Leases	1,655,809	$ 4,844,312
Loans and Leases Receivable, Net of Deferred Income	$ 2,787,784	$ 4,844,312
Percentage of Total NPLs	9.54%	25.99%
Commercial Real Estate Portfolio Segment [Member] \| Nonperforming Financial Instruments [Member] \| Other Non-owner Occupied Commercial Real Estate Loans [Member]
Nonaccrual Loans/Leases	$ 10,293,961	$ 1,243,728
Accruing TDRs	2,975,703
Loans and Leases Receivable, Net of Deferred Income	$ 13,269,664	$ 1,243,728
Percentage of Total NPLs	45.41%	6.67%
Finance Leases Portfolio Segment [Member]
Nonaccrual Loans/Leases	$ 1,966,716	$ 2,175,044
Loans and Leases Receivable, Net of Deferred Income	126,751,783	141,448,232
Finance Leases Portfolio Segment [Member] \| Nonperforming Financial Instruments [Member]
Nonaccrual Loans/Leases	1,966,716	2,175,044
Accruing TDRs	163,681	1,494,448
Loans and Leases Receivable, Net of Deferred Income	$ 2,130,397	$ 3,669,492
Percentage of Total NPLs	7.29%	19.68%
Residential Portfolio Segment [Member]
Accruing Past Due 90 Days or More	$ 270,413	$ 74,519
Nonaccrual Loans/Leases	973,947	1,363,806
Loans and Leases Receivable, Net of Deferred Income	309,287,535	258,646,265
Residential Portfolio Segment [Member] \| Nonperforming Financial Instruments [Member]
Accruing Past Due 90 Days or More	270,413	74,519
Nonaccrual Loans/Leases	973,947	1,363,806
Accruing TDRs	305,792	272,493
Loans and Leases Receivable, Net of Deferred Income	$ 1,550,152	$ 1,710,818
Percentage of Total NPLs	5.30%	9.18%
Consumer Portfolio Segment [Member]
Accruing Past Due 90 Days or More	$ 6,967	$ 14,152
Nonaccrual Loans/Leases	230,616	249,091
Loans and Leases Receivable, Net of Deferred Income	100,191,471	118,610,799
Consumer Portfolio Segment [Member] \| Nonperforming Financial Instruments [Member]
Accruing Past Due 90 Days or More	6,967	14,152
Nonaccrual Loans/Leases	230,616	249,091
Accruing TDRs	10,410	14,027
Loans and Leases Receivable, Net of Deferred Income	$ 247,993	$ 277,270
Percentage of Total NPLs	0.85%	1.49%

The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

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Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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