|
Fair Value of Financial Assets and Liabilities (Tables)
|
6 Months Ended |
|
Oct. 31, 2012
|
| Fair Value of Financial Assets and Liabilities [Abstract] |
|
| Summary of cash and cash equivalents |
| |
|
|
|
|
|
|
|
|
| (in thousands) |
|
October 31, 2012 |
|
|
April 30, 2012 |
|
|
Demand deposit accounts
|
|
$ |
41,427 |
|
|
$ |
45,361 |
|
|
Money market funds
|
|
|
3,689 |
|
|
|
288 |
|
|
U.S. Treasury bills
|
|
|
— |
|
|
|
7,499 |
|
|
Corporate bonds (U.S. Gov. guaranteed)
|
|
|
— |
|
|
|
21,219 |
|
| |
|
|
|
|
|
|
|
|
|
Total cash and cash equivalents
|
|
$ |
45,116 |
|
|
$ |
74,367 |
|
| |
|
|
|
|
|
|
|
|
|
| Summary of short-term investments |
| |
|
|
|
|
|
|
|
|
|
|
|
|
| (in thousands) |
|
Cost |
|
|
Gross Unrealized Losses |
|
|
Fair Value |
|
|
Available-for-sale securities:
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Certificates of deposit (U.S. Gov. guaranteed)
|
|
$ |
10,226 |
|
|
$ |
(8 |
) |
|
$ |
10,218 |
|
|
Corporate bonds
|
|
|
23,395 |
|
|
|
(9 |
) |
|
|
23,386 |
|
|
U.S. Treasury notes
|
|
|
62,814 |
|
|
|
(10 |
) |
|
|
62,804 |
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
Total short-term investments
|
|
$ |
96,435 |
|
|
$ |
(27 |
) |
|
$ |
96,408 |
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
The following table summarizes the Company’s short-term investments as of April 30, 2012:
| |
|
|
|
|
|
|
|
|
|
|
|
|
| |
|
Year Ended April 30, 2012 |
|
| |
|
Gross
Unrealized
|
|
| (in thousands) |
|
Cost |
|
|
Gains (Losses) |
|
|
Fair Value |
|
|
Available-for-sale securities:
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Certificates of deposit (U.S. Gov. guaranteed)
|
|
$ |
4,510 |
|
|
$ |
(14 |
) |
|
$ |
4,496 |
|
|
U.S. Treasury notes
|
|
|
28,126 |
|
|
|
(28 |
) |
|
|
28,099 |
|
|
Corporate bonds
|
|
|
18,245 |
|
|
|
(5 |
) |
|
|
18,239 |
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
Total short-term investments
|
|
$ |
50,881 |
|
|
$ |
(47 |
) |
|
$ |
50,834 |
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
| Summary of fair value of financial assets and liabilities |
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
|
Fair Value Measurements at October 31, 2012 |
|
|
Fair Value Measurements at April 30, 2012 |
|
| (in thousands) |
|
Level 1 |
|
|
Level 2 |
|
|
Level 3 |
|
|
Total |
|
|
Level 1 |
|
|
Level 2 |
|
|
Level 3 |
|
|
Total |
|
|
Assets:
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Cash equivalents:
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Money market funds
|
|
$ |
3,689 |
|
|
$ |
— |
|
|
$ |
— |
|
|
$ |
3,689 |
|
|
$ |
288 |
|
|
$ |
— |
|
|
$ |
— |
|
|
$ |
288 |
|
|
U.S. Treasury bills
|
|
|
— |
|
|
|
— |
|
|
|
— |
|
|
|
— |
|
|
|
7,499 |
|
|
|
— |
|
|
|
— |
|
|
|
7,499 |
|
|
Corporate bonds (U.S. Gov. guaranteed)
|
|
|
— |
|
|
|
— |
|
|
|
— |
|
|
|
— |
|
|
|
21,219 |
|
|
|
— |
|
|
|
— |
|
|
|
21,219 |
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Total cash equivalents
|
|
|
3,689 |
|
|
|
— |
|
|
|
— |
|
|
|
3,689 |
|
|
|
29,006 |
|
|
|
— |
|
|
|
— |
|
|
|
29,006 |
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Restricted cash
|
|
|
604 |
|
|
|
— |
|
|
|
— |
|
|
|
604 |
|
|
|
500 |
|
|
|
— |
|
|
|
— |
|
|
|
500 |
|
|
Short-term investments:
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Certificates of deposit (U.S. Gov. guaranteed)
|
|
|
10,218 |
|
|
|
— |
|
|
|
— |
|
|
|
10,218 |
|
|
|
4,496 |
|
|
|
— |
|
|
|
— |
|
|
|
4,496 |
|
|
Corporate bonds
|
|
|
23,386 |
|
|
|
— |
|
|
|
— |
|
|
|
23,386 |
|
|
|
18,239 |
|
|
|
— |
|
|
|
— |
|
|
|
18,239 |
|
|
U.S. Treasury notes
|
|
|
62,804 |
|
|
|
— |
|
|
|
— |
|
|
|
62,804 |
|
|
|
28,099 |
|
|
|
— |
|
|
|
— |
|
|
|
28,099 |
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Total short-term investments
|
|
|
96,408 |
|
|
|
— |
|
|
|
— |
|
|
|
96,408 |
|
|
|
50,834 |
|
|
|
— |
|
|
|
— |
|
|
|
50,834 |
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Total assets
|
|
$ |
100,701 |
|
|
$ |
— |
|
|
$ |
— |
|
|
$ |
100,701 |
|
|
$ |
80,340 |
|
|
$ |
— |
|
|
$ |
— |
|
|
$ |
80,340 |
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
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