Note 2 - Acquisitions - Purchased Loans As of the Acquisition Date (Details) - USD ($)	Oct. 01, 2017	Aug. 31, 2016
Guaranty Bank and Trust Company [Member]
Contractually required principal payments	$ 196,108,766
Nonaccretable discount	(1,147,198)
Principal cash flows expected to be collected	194,961,568
Accretable discount	(2,443,891)
Fair Value of acquired loans	192,517,677
Guaranty Bank and Trust Company [Member] \| Performing Financial Instruments [Member]
Contractually required principal payments	192,982,439
Nonaccretable discount
Principal cash flows expected to be collected	192,982,439
Accretable discount	(2,223,989)
Fair Value of acquired loans	190,758,450
Community State Bank [Member]
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
Community State Bank [Member] \| 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] \| Guaranty Bank and Trust Company [Member]
Contractually required principal payments	3,126,327
Nonaccretable discount	(1,147,198)
Principal cash flows expected to be collected	1,979,129
Accretable discount	(219,902)
Fair Value of acquired loans	$ 1,759,227
Receivables Acquired with Deteriorated Credit Quality [Member] \| Community State Bank [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=82894507&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=82894903&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=82894903&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=82894507&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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