Note 4 - Investment Securities (Details) - Investment Securities by Contractual Maturity (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015
Government agencies
Securities available for sale, less than one year, amortized cost	$ 1,945
Securities available for sale, one to five years, amortized cost	122,829
Securities available for sale, five to ten years, amortized cost	114,708
Securities available for sale, over ten years, amortized cost	25,678
Securities available for sale, less than one year, fair value	1,965
Securities available for sale, one to five years, fair value	125,470
Securities available for sale, five to ten years, fair value	117,529
Securities available for sale, over ten years, fair value	27,519
Government agencies
Securities held to maturity, one to five years, amortized cost	508
Securities held to maturity, one to five years, fair value	514
US Government Agencies Debt Securities [Member]
Government agencies
Securities available for sale, one to five years, amortized cost	7,614
Securities available for sale, five to ten years, amortized cost	23,282
Securities available for sale, one to five years, fair value	7,710
Securities available for sale, five to ten years, fair value	23,949
Government agencies
Securities held to maturity, one to five years, amortized cost	508
Securities held to maturity, one to five years, fair value	514
Mortgage-backed Securities, Issued by Private Enterprises [Member]
Government agencies
Securities available for sale, one to five years, amortized cost	75,592
Securities available for sale, five to ten years, amortized cost	53,959
Securities available for sale, over ten years, amortized cost	21,953
Securities available for sale, one to five years, fair value	77,428
Securities available for sale, five to ten years, fair value	55,009
Securities available for sale, over ten years, fair value	23,652
Municipal Securities [Member]
Government agencies
Securities available for sale, less than one year, amortized cost	1,945
Securities available for sale, one to five years, amortized cost	24,240
Securities available for sale, five to ten years, amortized cost	23,969
Securities available for sale, over ten years, amortized cost	3,725
Securities available for sale, less than one year, fair value	1,965
Securities available for sale, one to five years, fair value	24,947
Securities available for sale, five to ten years, fair value	25,142
Securities available for sale, over ten years, fair value	3,867
Corporate Debt Securities [Member]
Government agencies
Securities available for sale, one to five years, amortized cost	15,383
Securities available for sale, five to ten years, amortized cost	13,498
Securities available for sale, one to five years, fair value	15,385
Securities available for sale, five to ten years, fair value	$ 13,429

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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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Fair value of held-to-maturity 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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Carrying amount of debt securities accounted for as held-to-maturity, net of adjustments including, but not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized, and fair value hedge accounting adjustments, maturing in the next fiscal year through the fifth fiscal year following the latest fiscal year.

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