Note 7 - Investments in Marketable Securities (Detail) - Amortized Cost and Estimated Fair Value of Debt Securities as Available for Sale (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Within 1 year	$ 7,704	$ 5,280
Within 1 year	7,775	5,298
1to 5 years	54,256	44,923
1to 5 years	55,588	45,734
6to 10 years	21,998	21,993
6to 10 years	23,180	22,768
Over 10 years	850	9,553
Over 10 years	895	9,825
	84,808	81,749
	$ 87,438	$ 83,625

Amount of available-for-sale debt securities at cost, net of adjustments, 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 any cumulative-effect adjustments, as defined) and fair value hedge accounting adjustments.

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