Note 8 - Disclosures about Fair Value of Assets and Liabilities (Detail) - Fair Value of Financial Instruments (USD $)	Mar. 31, 2013	Dec. 31, 2012	Mar. 31, 2012	Dec. 31, 2011
Financial assets:
Cash and cash equivalents	$ 42,694,971	$ 41,663,405	$ 35,708,676	$ 26,574,082
Held-to-maturity securities	136,350	181,042
Federal Home Loan Bank stock	3,133,600	3,805,500
Mortgage loans held for sale	1,314,333	2,843,757
Loans, net	451,892,450	465,531,973
Financial liabilities:
Deposits	503,644,217	500,014,715
Federal Home Loan Bank advances	52,950,000	68,050,000
Securities sold under agreements to repurchase	25,000,000	25,000,000
Subordinated debentures, carrying amount	15,465,000	15,465,000
Interest payable	347,804	399,684
Commitments to Extend Credit [Member]
Unrecognized financial instruments (net of contractual value):
Commitments to extend credit	0	0
Commitments to extend credit	0	0
Unused lines of Credit [Member]
Unrecognized financial instruments (net of contractual value):
Commitments to extend credit	0	0
Commitments to extend credit	0	0
Fair Value, Inputs, Level 1 [Member]
Financial assets:
Cash and cash equivalents	42,694,971	41,663,405
Cash and cash equivalents	42,694,971	41,663,405
Fair Value, Inputs, Level 2 [Member]
Financial assets:
Held-to-maturity securities	136,350	181,042
Held-to-maturity securities	140,447	193,482
Federal Home Loan Bank stock	3,133,600	3,805,500
Mortgage loans held for sale	1,314,333	2,843,757
Mortgage loans held for sale	1,314,333	2,843,757
Interest receivable	1,925,991	2,055,369
Financial liabilities:
Deposits	503,644,217	500,014,715
Deposits	500,314,025	500,580,070
Federal Home Loan Bank advances	52,950,000	68,050,000
Federal Home Loan Bank advances	56,347,719	72,035,160
Securities sold under agreements to repurchase	25,000,000	25,000,000
Securities sold under agreements to repurchase	25,120,201	25,114,464
Interest payable	347,804	399,684
Fair Value, Inputs, Level 3 [Member]
Financial assets:
Loans, net	451,892,450	465,531,973
Loans, net	466,449,679	475,374,676
Financial liabilities:
Subordinated debentures, carrying amount	15,465,000	15,465,000
Subordinated debentures, fair value	$ 15,465,000	$ 15,465,000