Cash And Cash Equivalents And Investments (Schedule Of Available-For-Sale Investments) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Cash And Cash Equivalents And Investments [Abstract]
Original stated term to maturity of available-for-sale- investments, Less than one year	$ 160,607	$ 159,671
Original stated term to maturity of available-for-sale- investments, Greater than ten years	10,415	11,311
Original stated term to maturity of available-for-sale- investments, Total	$ 171,022	$ 170,982

This item represents the fair value of debt securities which are expected to mature within one year of the balance sheet date and which are categorized neither as held-to-maturity nor trading securities.

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For an unclassified balance sheet, total of debt securities categorized neither as held-to-maturity nor trading.

+ References

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