Note 4 - Loans Leases Receivable - Aging of the Loan Lease Portfolio (Details) - USD ($)	Sep. 30, 2018	Dec. 31, 2017
Current	$ 3,609,446,916	$ 2,929,430,446
Accruing Past Due 90 Days or More	1,409,355	88,671
Financing Receivable, Recorded Investment, Nonaccrual Status	23,576,285	11,441,234
Loans and leases	$ 3,644,099,503	$ 2,956,713,493
Current as a percentage of total loan/lease portfolio	99.05%	99.08%
Accruing past due 90 days or more as a percentage of total loan/lease portfolio	0.04%	0.00%
Nonaccrual Loans/Leases as a percentage of total loan/lease portfolio	0.65%	0.39%
Loans and leases as a percentage of total loan/lease portfolio	100.00%	100.00%
Financing Receivables, 30 to 59 Days Past Due [Member]
Past Due	$ 7,250,850	$ 14,795,578
Past due as a percentage of total loan/lease portfolio	0.20%	0.50%
Financing Receivables, 60 to 89 Days Past Due [Member]
Past Due	$ 2,416,097	$ 957,563
Past due as a percentage of total loan/lease portfolio	0.07%	0.03%
Commercial Portfolio Segment [Member]
Current	$ 1,371,826,021	$ 1,124,734,486
Financing Receivable, Recorded Investment, Nonaccrual Status	8,046,588	1,231,353
Loans and leases	1,380,542,524	1,134,516,315
Commercial Portfolio Segment [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member]
Past Due	143,866	8,306,829
Commercial Portfolio Segment [Member] \| Financing Receivables, 60 to 89 Days Past Due [Member]
Past Due	526,049	243,647
Commercial Real Estate Portfolio Segment [Member]
Loans and leases	1,727,326,190	1,303,491,882
Commercial Real Estate Portfolio Segment [Member] \| Owner Occupied Commercial Real Estate Loans [Member]
Current	447,031,462	331,868,142
Financing Receivable, Recorded Investment, Nonaccrual Status	408,648	333,900
Loans and leases	449,056,125	332,742,477
Commercial Real Estate Portfolio Segment [Member] \| Construction Loans [Member]
Current	217,512,489	181,558,092
Accruing Past Due 90 Days or More	1,131,975
Financing Receivable, Recorded Investment, Nonaccrual Status	1,655,809	4,844,312
Loans and leases	224,295,259	186,402,404
Commercial Real Estate Portfolio Segment [Member] \| Other Non-owner Occupied Commercial Real Estate Loans [Member]
Current	1,043,267,553	782,526,249
Financing Receivable, Recorded Investment, Nonaccrual Status	10,293,961	1,243,728
Loans and leases	1,053,974,806	784,347,000
Commercial Real Estate Portfolio Segment [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member] \| Owner Occupied Commercial Real Estate Loans [Member]
Past Due	1,506,334	540,435
Commercial Real Estate Portfolio Segment [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member] \| Construction Loans [Member]
Past Due	3,994,986
Commercial Real Estate Portfolio Segment [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member] \| Other Non-owner Occupied Commercial Real Estate Loans [Member]
Past Due	413,292	572,877
Commercial Real Estate Portfolio Segment [Member] \| Financing Receivables, 60 to 89 Days Past Due [Member] \| Owner Occupied Commercial Real Estate Loans [Member]
Past Due	109,681
Commercial Real Estate Portfolio Segment [Member] \| Financing Receivables, 60 to 89 Days Past Due [Member] \| Other Non-owner Occupied Commercial Real Estate Loans [Member]
Past Due		4,146
Finance Leases Portfolio Segment [Member]
Current	123,407,592	137,708,397
Financing Receivable, Recorded Investment, Nonaccrual Status	1,966,716	2,175,044
Loans and leases	126,751,783	141,448,232
Finance Leases Portfolio Segment [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member]
Past Due	1,153,460	1,305,191
Finance Leases Portfolio Segment [Member] \| Financing Receivables, 60 to 89 Days Past Due [Member]
Past Due	224,015	259,600
Residential Portfolio Segment [Member]
Current	306,900,388	253,261,821
Accruing Past Due 90 Days or More	270,413	74,519
Financing Receivable, Recorded Investment, Nonaccrual Status	973,947	1,363,806
Loans and leases	309,287,535	258,646,265
Residential Portfolio Segment [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member]
Past Due		3,552,709
Residential Portfolio Segment [Member] \| Financing Receivables, 60 to 89 Days Past Due [Member]
Past Due	1,142,787	393,410
Consumer Portfolio Segment [Member]
Current	99,501,411	117,773,259
Accruing Past Due 90 Days or More	6,967	14,152
Financing Receivable, Recorded Investment, Nonaccrual Status	230,616	249,091
Loans and leases	100,191,471	118,610,799
Consumer Portfolio Segment [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member]
Past Due	38,912	517,537
Consumer Portfolio Segment [Member] \| Financing Receivables, 60 to 89 Days Past Due [Member]
Past Due	$ 413,565	$ 56,760

Reflects the percentage derived from dividing loans accruing past due 90 days or more by total loans.

No definition available.

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- Definition

Reflects the percentage derived from dividing current loans by total loans.

+ References

No definition available.

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Reflects the percentage derived from dividing nonaccrual loans by total loans.

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No definition available.

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Reflects the percentage derived from dividing past due loans by total loans.

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Recorded investment in financing receivables that are 90 days or more past due and still accruing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
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Financing receivables that are current.

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

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-Publisher FASB
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- Definition

Recorded Investment in financing receivables that are past due at 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.

+ References

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Reflects the percentage derived from dividing impaired loans on which interest has ceased to be accrued by total loans.

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No definition available.

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