Cash and Cash Equivalents and Short-term Investments (Details 2) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014
Gross unrealized losses of cash and cash equivalents and short-term investments
Available-for-sale securities, less than 12 months	$ 20
Available-for-sale securities, more than 12 months	361
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	37
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	20
Available-for-sale securities, more than 12 months	361
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	37
Mortgage-CMO debt securities
Gross unrealized losses of cash and cash equivalents and short-term investments
Available-for-sale securities, less than 12 months	20
Available-for-sale securities, continuous unrealized loss position, less than 12 Months, aggregate losses	1
Asset-backed debt securities
Gross unrealized losses of cash and cash equivalents and short-term investments
Available-for-sale securities, more than 12 months	361
Available-for-sale securities, continuous unrealized loss position, 12 months or longer, aggregate losses	$ 37