Marketable Securities, Available-for-sale (Details 2) (USD $) In Thousands	Sep. 30, 2011	Dec. 31, 2010
Contractual maturity:
Marketable securities, available-for-sale	$ 338,752	$ 437,795
Total debt securities
Contractual maturity:
Maturing in one year or less	115,922	22,244
Maturing after one year through three years	133,394	299,381
Maturing after three years	48,747	11,006
Marketable securities, available-for-sale	298,063	332,631
Time Deposits and Short-term Pooled Investments
Contractual maturity:
Marketable securities, available-for-sale	$ 40,689	$ 105,164

For an unclassified balance sheet, this item represents investments in debt and equity securities which are categorized neither as held-to-maturity nor trading.

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+ Details