Note 6 - Marketable Securities (Detail) - Amortized Cost and Estimated Fair Value of Investments in Available-For-Sale Debt Securities: (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
Mature in one year or less	$ 214,784
Mature in one year or less	215,589
Mature after one year through three years	19,550
Mature after one year through three years	19,854
Mature in more than three years	15,753
Mature in more than three years	15,572
Total	250,087
Total	$ 251,015

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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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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