Note 5 - Marketable Securities (Detail) - Amortized Cost and Estimated Fair Value of Investments in Available-For-Sale Securities (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Mature in one year or less	$ 229,591	$ 256,764
Mature in one year or less	229,664	257,050
Mature after one year through three years	19,645	60,473
Mature after one year through three years	19,809	60,805
Total	249,236	317,237
Total	$ 249,473	$ 317,855

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

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Amount of available-for-sale debt securities at cost, net of adjustments, which 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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- Definition

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

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- Definition

Amount of debt securities categorized neither as held-to-maturity nor trading.

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