| Schedule of Short-Term Investments |
At April 30, 2018, short-term investments consisted of the following (in thousands):
|
|
|
|
|
|
|
Gross |
|
|
Gross |
|
|
Estimated |
|
|
|
|
Amortized |
|
|
unrealized |
|
|
unrealized |
|
|
fair |
|
|
|
|
cost |
|
|
gains |
|
|
losses |
|
|
value |
|
|
Available-for-sale securities: |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Certificates of deposits |
|
$ |
11,030 |
|
|
$ |
4 |
|
|
$ |
— |
|
|
$ |
11,034 |
|
|
Asset-backed securities |
|
|
70,068 |
|
|
|
1 |
|
|
|
(615 |
) |
|
|
69,454 |
|
|
Commercial paper |
|
|
21,286 |
|
|
|
1 |
|
|
|
(9 |
) |
|
|
21,278 |
|
|
Corporate notes and bonds |
|
|
155,457 |
|
|
|
24 |
|
|
|
(1,011 |
) |
|
|
154,470 |
|
|
Foreign government bonds |
|
|
1,503 |
|
|
|
— |
|
|
|
(23 |
) |
|
|
1,480 |
|
|
Mortgage backed securities |
|
|
13,027 |
|
|
|
2 |
|
|
|
(100 |
) |
|
|
12,929 |
|
|
U.S. agency obligations |
|
|
64,765 |
|
|
|
1 |
|
|
|
(59 |
) |
|
|
64,707 |
|
|
U.S. treasury securities |
|
|
122,934 |
|
|
|
1 |
|
|
|
(218 |
) |
|
|
122,717 |
|
|
Total available-for-sale securities |
|
$ |
460,070 |
|
|
$ |
34 |
|
|
$ |
(2,035 |
) |
|
$ |
458,069 |
|
|
|
|
At January 31, 2018, short-term investments consisted of the following (in thousands):
|
|
|
|
|
|
|
Gross |
|
|
Gross |
|
|
Estimated |
|
|
|
|
Amortized |
|
|
unrealized |
|
|
unrealized |
|
|
fair |
|
|
|
|
cost |
|
|
gains |
|
|
losses |
|
|
value |
|
|
Available-for-sale securities: |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Asset-backed securities |
|
$ |
67,875 |
|
|
$ |
— |
|
|
$ |
(424 |
) |
|
$ |
67,451 |
|
|
Commercial paper |
|
|
19,926 |
|
|
|
— |
|
|
|
(12 |
) |
|
|
19,914 |
|
|
Corporate notes and bonds |
|
|
160,499 |
|
|
|
1 |
|
|
|
(759 |
) |
|
|
159,741 |
|
|
Foreign government bonds |
|
|
1,504 |
|
|
|
— |
|
|
|
(18 |
) |
|
|
1,486 |
|
|
Mortgage backed securities |
|
|
11,555 |
|
|
|
— |
|
|
|
(75 |
) |
|
|
11,480 |
|
|
U.S. agency obligations |
|
|
71,206 |
|
|
|
1 |
|
|
|
(76 |
) |
|
|
71,131 |
|
|
U.S. treasury securities |
|
|
110,707 |
|
|
|
5 |
|
|
|
(136 |
) |
|
|
110,576 |
|
|
Total available-for-sale securities |
|
$ |
443,272 |
|
|
$ |
7 |
|
|
$ |
(1,500 |
) |
|
$ |
441,779 |
|
|
|
|
|
| Summary of Estimated Fair Value of Short-Term Investments, Designated as Available-for-Sale and Classified by Contractual Maturity |
The following table summarizes the estimated fair value of our short-term investments, designated as available-for-sale and classified by the contractual maturity date of the securities as of the dates shown (in thousands):
|
|
|
April 30, |
|
|
January 31, |
|
|
|
|
2018 |
|
|
2018 |
|
|
Due in one year or less |
|
$ |
282,866 |
|
|
$ |
308,172 |
|
|
Due in greater than one year |
|
|
175,203 |
|
|
|
133,607 |
|
|
Total |
|
$ |
458,069 |
|
|
$ |
441,779 |
|
|
|
|
|
| Schedule of Fair Values and Gross Unrealized Losses of Available-for-Sale Securities Aggregated by Investment Category |
The following table shows the fair values and the gross unrealized losses of these available-for-sale securities aggregated by investment category as of April 30, 2018 (in thousands):
|
|
|
|
|
|
|
Gross |
|
|
|
|
Fair |
|
|
unrealized |
|
|
|
|
value |
|
|
losses |
|
|
Asset-backed securities |
|
$ |
67,441 |
|
|
$ |
(615 |
) |
|
Commercial paper |
|
|
16,312 |
|
|
|
(9 |
) |
|
Corporate notes and bonds |
|
|
130,825 |
|
|
|
(1,011 |
) |
|
Foreign government bonds |
|
|
1,480 |
|
|
|
(23 |
) |
|
Mortgage backed securities |
|
|
11,425 |
|
|
|
(100 |
) |
|
U.S. agency obligations |
|
|
58,526 |
|
|
|
(59 |
) |
|
U.S. treasury securities |
|
|
113,148 |
|
|
|
(218 |
) |
|
|
|
The following table shows the fair values and the gross unrealized losses of these available-for-sale securities aggregated by investment category as of January 31, 2018 (in thousands):
|
|
|
|
|
|
|
Gross |
|
|
|
|
Fair |
|
|
unrealized |
|
|
|
|
value |
|
|
losses |
|
|
Asset-backed securities |
|
$ |
65,690 |
|
|
$ |
(424 |
) |
|
Commercial paper |
|
|
19,914 |
|
|
|
(12 |
) |
|
Corporate notes and bonds |
|
|
155,419 |
|
|
|
(759 |
) |
|
Foreign government bonds |
|
|
1,485 |
|
|
|
(18 |
) |
|
Mortgage backed securities |
|
|
11,481 |
|
|
|
(75 |
) |
|
U.S. agency obligations |
|
|
66,655 |
|
|
|
(76 |
) |
|
U.S. treasury securities |
|
|
82,147 |
|
|
|
(136 |
) |
|
|
|
|