Note 8 - Investments in Marketable Securities (Detail) - Amortized Cost and Estimated Fair Value of Debt Securities as Available for Sale (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Within 1 year	$ 8,868	$ 5,280
Within 1 year	8,918	5,298
1 to 5 years	80,910	44,923
1 to 5 years	82,801	45,734
6 to 10 years	40,670	21,993
6 to 10 years	41,856	22,768
Over 10 years	1,630	9,553
Over 10 years	1,632	9,825
	132,078	81,749
	$ 135,207	$ 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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