Cash and Cash Equivalents and Short-term Investments (Details 4) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013
Debt securities:
Due after one year through five years	$ 15,113
Due in more than five years	4,433
Total debt securities	$ 19,546

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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