4. Marketable Securities
The following table is a summary of available-for-sale debt securities and money market funds recorded in cash equivalents or marketable securities in the Company's Consolidated Balance Sheets. Estimated fair values of available-for-sale securities are generally based on prices obtained from commercial pricing services:
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
December 31, 2011 |
|
December 31, 2010 |
|
(in thousands) |
|
Amortized
Cost |
|
Gross
Unrealized
Gains |
|
Gross
Unrealized
Losses |
|
Estimated
Fair Value |
|
Amortized
Cost |
|
Gross
Unrealized
Gains |
|
Gross
Unrealized
Losses |
|
Estimated
Fair Value |
|
U.S. government securities |
|
$ |
66,150 |
|
$ |
24 |
|
$ |
— |
|
$ |
66,174 |
|
$ |
25,966 |
|
$ |
10 |
|
$ |
— |
|
$ |
25,976 |
|
U.S. government agencies |
|
|
93,183 |
|
|
9 |
|
|
(17 |
) |
|
93,175 |
|
|
54,625 |
|
|
30 |
|
|
(7 |
) |
|
54,648 |
|
U.S. corporate notes |
|
|
2,707 |
|
|
— |
|
|
(2 |
) |
|
2,705 |
|
|
34,695 |
|
|
9 |
|
|
(9 |
) |
|
34,695 |
|
U.S. commercial paper |
|
|
34,973 |
|
|
3 |
|
|
— |
|
|
34,976 |
|
|
97,221 |
|
|
— |
|
|
— |
|
|
97,221 |
|
Money market funds |
|
|
38,721 |
|
|
— |
|
|
— |
|
|
38,721 |
|
|
91,805 |
|
|
— |
|
|
— |
|
|
91,805 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Total |
|
|
235,734 |
|
|
36 |
|
|
(19 |
) |
|
235,751 |
|
|
304,312 |
|
|
49 |
|
|
(16 |
) |
|
304,345 |
|
Less amounts classified as cash equivalents |
|
|
(38,721 |
) |
|
— |
|
|
— |
|
|
(38,721 |
) |
|
(157,151 |
) |
|
— |
|
|
— |
|
|
(157,151 |
) |
Less amounts classified as restricted cash |
|
|
(893 |
) |
|
— |
|
|
— |
|
|
(893 |
) |
|
(893 |
) |
|
— |
|
|
— |
|
|
(893 |
) |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Amounts classified as marketable securities |
|
$ |
196,120 |
|
$ |
36 |
|
$ |
(19 |
) |
$ |
196,137 |
|
$ |
146,268 |
|
$ |
49 |
|
$ |
(16 |
) |
$ |
146,301 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
The following table provides the net realized gains (losses) on marketable securities for the periods presented:
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|
|
|
|
|
|
|
|
|
|
|
|
Year Ended
December 31, |
|
(in thousands) |
|
2011 |
|
2010 |
|
2009 |
|
Realized gains |
|
$ |
— |
|
$ |
3 |
|
$ |
— |
|
Realized losses |
|
|
(2 |
) |
|
— |
|
|
— |
|
|
|
|
|
|
|
|
|
Net realized gains (losses) |
|
$ |
(2 |
) |
$ |
3 |
|
$ |
— |
|
|
|
|
|
|
|
|
|
The Company realized no gains or losses in 2011 and 2010 that were previously classified as unrealized gains and losses in accumulated other comprehensive income at December 31, 2010 and 2009, respectively.
The following table provides the breakdown of the marketable securities with unrealized losses at December 31, 2011:
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|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
In loss position for
less than 12 months |
|
In loss position for
more than 12 months |
|
Total |
|
(in thousands) |
|
Fair Value |
|
Estimated
Gross
Unrealized
Losses |
|
Fair Value |
|
Estimated
Gross
Unrealized
Losses |
|
Fair Value |
|
Estimated
Gross
Unrealized
Losses |
|
U.S. government agencies |
|
$ |
47,807 |
|
$ |
(17 |
) |
$ |
— |
|
$ |
— |
|
$ |
47,807 |
|
$ |
(17 |
) |
U.S. corporate notes |
|
|
2,754 |
|
|
(2 |
) |
|
— |
|
|
— |
|
|
2,754 |
|
|
(2 |
) |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Total |
|
$ |
50,561 |
|
$ |
(19 |
) |
$ |
— |
|
$ |
— |
|
$ |
50,561 |
|
$ |
(19 |
) |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
At December 31, 2011, all of the available-for-sale debt securities had contractual maturities within twelve months and the average duration of marketable securities was approximately five months. The Company does not intend to sell the investments which are in an unrealized loss position and it is unlikely that the Company will be required to sell the investments before recovery of their amortized cost basis, which may be maturity. The Company has determined that the gross unrealized losses on its marketable securities at December 31, 2011 were temporary in nature. |