Note 2 - Investment Securities (Detail) - Amortized Cost and Fair Value of Securities by Contractual Maturity (USD $)	Sep. 30, 2012
Securities held to maturity:
Due in one year or less	$ 100,000
Due in one year or less	100,000
Due after one year through five years	550,000
Due after one year through five years	550,000
	650,000
	650,000
Securities available for sale:
Due in one year or less	2,251,717
Due in one year or less	2,257,998
Due after one year through five years	40,236,390
Due after one year through five years	40,681,663
Due after five years	385,715,495
Due after five years	390,465,992
Securities Available for Sale - amortized cost	580,796,837
Securities Available for Sale - fair value	590,701,449
Total [Member]
Securities available for sale:
Securities Available for Sale - amortized cost	428,203,602
Securities Available for Sale - fair value	433,405,653
Residential Mortgage Backed Securities [Member]
Securities available for sale:
Securities Available for Sale - amortized cost	151,264,044
Securities Available for Sale - fair value	155,690,575
Debt Securities [Member]
Securities available for sale:
Securities Available for Sale - amortized cost	1,329,191
Securities Available for Sale - fair value	$ 1,605,221

Available for sale securities debt maturities due after five years amortized cost.

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Amount of available-for-sale debt securities at cost, net of adjustments, maturing in the second fiscal year through the fifth fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings (less any cumulative-effect adjustments, as defined) and fair value hedge accounting adjustments.

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