Cash and Cash Equivalents and Short-term Investments (Details 5) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012
Debt securities:
Due in one year or less	$ 180
Due after one year through five years	17,900
Due in more than five years	16,990
Total debt securities	$ 35,070

Amount of debt securities categorized neither as held-to-maturity nor trading.

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