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	Mar. 31, 2013	Dec. 31, 2012
Within 1 year	$ 8,635	$ 8,868
Within 1 year	8,678	8,918
1 to 5 years	76,815	80,910
1 to 5 years	78,669	82,801
6 to 10 years	46,997	40,670
6 to 10 years	47,435	41,856
Over 10 years		1,630
Over 10 years		1,632
	132,447	132,078
	$ 134,782	$ 135,207

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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