Note 17 - Mortgage Banking Activities (Details Textual) - USD ($)	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Servicing Asset at Amortized Cost	$ 2,148,905	$ 1,265,589
Servicing Asset at Fair Value, Additions	391,499	315,122
Amortization of Mortgage Servicing Rights (MSRs)	286,575	227,648	$ 213,210
Servicing Asset at Fair Value, Amount	3,128,000	2,301,000
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Principal Amount Outstanding on Loans Held-for-sale or Securitization or Asset-backed Financing Arrangement	84,600,000
Payments for (Proceeds from) Mortgage Servicing Rights	778,000
Serviced for Others [Member]
Principal Amount Outstanding on Loans Held-for-sale or Securitization or Asset-backed Financing Arrangement	$ 371,956,972	$ 297,493,516

The periodic amortization (in proportion to and over the period of estimated net servicing income or loss) of capitalized servicing rights, which contractually entitle the servicer to receive fees and ancillary revenues for performing billing, collection, disbursement and recordkeeping services in connection with a mortgage portfolio. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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-Name Accounting Standards Codification
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The net cash outflow or inflow associated with acquisition or sale of mortgage servicing rights which is the net carrying value of capitalized servicing rights, which contractually entitle the servicer to receive fees and ancillary revenues for performing billing, collection, disbursement and recordkeeping services in connection with a mortgage portfolio. Rights may be obtained via (1) acquisition or assumption of a servicing obligation that does not relate to financial assets of the servicer or its consolidated affiliates; or (2) by originating mortgage loans and then (a) transferring the loans to a Variable Interest Entity (VIE) in a transaction that meets the necessary transfer and classification requirements, or (b) transferring the loans in a transaction that meets the requirements for sale accounting.

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This is the principal amount outstanding for loans which are in the process of being securitized as of the date of the statement of financial position (across all types of loans).

+ References

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Amortized amount of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

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The value of new servicing assets, subsequently measured at fair value, acquired or created during the current period through purchases or from transfers of financial assets.

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Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

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