Note 4 - Debt and Equity Securities (Details) - Securities Available for Sale by Contractual Maturity (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Note 4 - Debt and Equity Securities (Details) - Securities Available for Sale by Contractual Maturity [Line Items]
Due in one year or less	$ 44,295
Due in one year or less	44,424
Due after one year through five years	41,225
Due after one year through five years	43,266
Due after five years through ten years	63,537
Due after five years through ten years	63,354
Due after ten years	138,801
Due after ten years	137,093
Securities Available for Sale, Amortized Cost	1,052,801
Securities Available for Sale, Fair Value	1,058,682	1,017,790
Available For Sale Securities Excluding Mortgage Backed Securities [Member]
Note 4 - Debt and Equity Securities (Details) - Securities Available for Sale by Contractual Maturity [Line Items]
Securities Available for Sale, Amortized Cost	287,858
Securities Available for Sale, Fair Value	288,137	261,634
Collateralized Mortgage Backed Securities [Member]
Note 4 - Debt and Equity Securities (Details) - Securities Available for Sale by Contractual Maturity [Line Items]
Securities Available for Sale, Amortized Cost	764,943
Securities Available for Sale, Fair Value	$ 770,545	$ 756,156

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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 of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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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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