Note 2 - Securities - Debt Securities by Maturity (Details)	Sep. 30, 2016 USD ($)
Collateralized Mortgage Backed Securities [Member]
Mortgage-backed securities	1.77%
Mortgage-backed securities	$ 51,671,000
Mortgage-backed securities	$ 52,569,000
Other Debt Obligations [Member]
Mortgage-backed securities	4.60%
Mortgage-backed securities	$ 1,970,000
Mortgage-backed securities	$ 1,987,000
Due in 2016	2.07%
Due in 2016	$ 14,095,000
Due in 2016	$ 14,030,000
Due in 2017 through 2021	1.83%
Due in 2017 through 2021	$ 116,939,000
Due in 2017 through 2021	$ 117,856,000
Due in 2022 through 2026	2.78%
Due in 2022 through 2026	$ 69,857,000
Due in 2022 through 2026	$ 70,885,000
Due in 2027 and beyond	2.86%
Due in 2027 and beyond	$ 67,993,000
Due in 2027 and beyond	$ 68,116,000
	2.27%
Available-for-sale Debt Securities, Amortized Cost Basis	$ 322,525,000
	$ 325,443,000

The aggregate weighted average yield of a securities portfolio.

No definition available.

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The weighted average yield of a securities portfolio with due dates after 10 years.

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The weighted average yield of a securities portfolio with due dates before 5 years and before 10 years.

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The weighted average yield of a securities portfolio with due dates after 1 year and before 5 years.

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The weighted average yield of securities portfolio with due dates in less than 1 year.

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The weighted average yield of a securities portfolio with no single maturity date defined.

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This item represents the cost of debt securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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Amount after adjustments of available-for-sale debt securities at cost, maturing in the sixth fiscal year through the tenth 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 cumulative-effect adjustments, and fair value hedge accounting adjustments. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Fair value of available-for-sale debt securities maturing in the sixth fiscal year through the tenth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount after adjustments of available-for-sale debt securities at cost, 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 cumulative-effect adjustments, and fair value hedge accounting adjustments. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Fair value of available-for-sale debt securities maturing in the second fiscal year through the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount after adjustments of available-for-sale debt securities at cost, maturing after the tenth 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 cumulative-effect adjustments, and fair value hedge accounting adjustments. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Fair value of available-for-sale debt securities maturing after the tenth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount after adjustments of available-for-sale debt securities at cost, maturing in the next 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 cumulative-effect adjustments, and fair value hedge accounting adjustments. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Fair value of available-for-sale debt securities maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of available-for-sale debt securities at cost, net of adjustments, that do not have a single maturity date and which the entity has decided to disclose separately rather than allocating the cost over several maturity groupings. 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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Amount of available-for-sale debt securities at fair value that do not have a single maturity date and which the entity has decided to disclose separately rather than allocating the fair value over several maturity groupings.

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Amount of debt securities categorized neither as held-to-maturity nor trading.

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