Fair Value (Details 1) (USD $) In Thousands	Sep. 30, 2011	Dec. 31, 2010
Maturities of short-term investments
Less than one year	$ 37,888	$ 21,174
Due in 1-2 years	11,555	2,664
Due in 3-30 years	16,205	0
Total	$ 65,648	$ 23,838

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

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+ Details