|
Cash, Cash Equivalents and Short-term Investments (Details 2) (USD $)
In Thousands, unless otherwise specified |
Jul. 31, 2013
|
Jan. 31, 2013
|
|---|---|---|
| Available-for-sale securities | ||
| Adjusted Cost | $ 33,891 | $ 66,272 |
| Unrealized Losses | (3) | |
| Fair Value | 33,891 | 66,269 |
|
Money market funds
|
||
| Available-for-sale securities | ||
| Adjusted Cost | 18,587 | 32,522 |
| Fair Value | 18,587 | 32,522 |
|
Commercial paper
|
||
| Available-for-sale securities | ||
| Adjusted Cost | 12,098 | 24,093 |
| Unrealized Losses | (1) | |
| Fair Value | 12,098 | 24,092 |
|
Corporate debt securities
|
||
| Available-for-sale securities | ||
| Adjusted Cost | 3,206 | 9,657 |
| Unrealized Losses | (2) | |
| Fair Value | $ 3,206 | $ 9,655 |