Cash and Cash Equivalents and Short-term Investments (Details 3) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013
Gross unrealized losses of cash and cash equivalents and short-term investments
Available-for-sale securities, less than 12 months	$ 575
Available-for-sale securities, more than 12 months	614
Available-for-sale securities, continuous unrealized loss position, less than 12 Months, aggregate losses	(3)
Available-for-sale securities, continuous unrealized loss position, 12 months or longer, aggregate losses	(88)
Available-for-sale debt securities
Gross unrealized losses of cash and cash equivalents and short-term investments
Available-for-sale securities, less than 12 months	575
Available-for-sale securities, more than 12 months	614
Available-for-sale securities, continuous unrealized loss position, less than 12 Months, aggregate losses	(3)
Available-for-sale securities, continuous unrealized loss position, 12 months or longer, aggregate losses	(88)
Mortgage-CMO debt securities
Gross unrealized losses of cash and cash equivalents and short-term investments
Available-for-sale securities, less than 12 months	21
Available-for-sale securities, more than 12 months	108
Available-for-sale securities, continuous unrealized loss position, less than 12 Months, aggregate losses	(2)
Available-for-sale securities, continuous unrealized loss position, 12 months or longer, aggregate losses	(1)
Asset-backed debt securities
Gross unrealized losses of cash and cash equivalents and short-term investments
Available-for-sale securities, less than 12 months	554
Available-for-sale securities, more than 12 months	506
Available-for-sale securities, continuous unrealized loss position, less than 12 Months, aggregate losses	(1)
Available-for-sale securities, continuous unrealized loss position, 12 months or longer, aggregate losses	$ (87)