Note 2 - Acquisition of Community State Bank and Common Stock Offering - Purchased Loans As of the Acquisition Date (Details) - Community State Bank [Member]	Aug. 31, 2016 USD ($)
Contractually required principal payments	$ 435,748,088
Nonaccretable discount	(4,525,223)
Principal cash flows expected to be collected	431,222,865
Accretable discount	(12,193,588)
Fair Value of acquired loans	419,029,277
Performing Financial Instruments [Member]
Contractually required principal payments	427,398,400
Nonaccretable discount
Principal cash flows expected to be collected	427,398,400
Accretable discount	(11,916,009)
Fair Value of acquired loans	415,482,391
Receivables Acquired with Deteriorated Credit Quality [Member]
Contractually required principal payments	8,349,688
Nonaccretable discount	(4,525,223)
Principal cash flows expected to be collected	3,824,465
Accretable discount	(277,579)
Fair Value of acquired loans	$ 3,546,886

Fair value at acquisition of acquired loans accounted for as debt securities with evidence of deterioration of credit quality.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 15
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=27045933&loc=d3e13503-111538

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

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Amount of cash flows expected to be collected at acquisition of acquired loans accounted for as debt securities with evidence of deterioration of credit quality.

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Amount of contractually required payments receivable at acquisition of acquired loans accounted for as debt securities with evidence of deterioration of credit quality.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 15
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=27045933&loc=d3e13503-111538

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The aggregate excess of a loan's cash flows expected to be collected over the investor's initial investment in the loan. This relates to loans with deteriorating of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

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