Short-Term Investments (Schedule Of Contractual Maturities Of Short-Term Investments) (Details) (USD $) In Thousands	Sep. 30, 2011	Dec. 31, 2010
Short-Term Investments [Abstract]
Due within 1 year	$ 247,370
After 1 but within 5 years	74,468
After 5 but within 10 years
After 10 years	16,591
Total	$ 338,429	$ 278,142

Total of debt securities categorized neither as held-to-maturity nor trading which are intended be sold or mature within one year from the balance sheet date or the normal operating cycle, whichever is longer.

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+ Details