|
Note 6. Cash, Cash Equivalents, and Marketable Securities (Details) - Available For Sale (USD $)
|
Dec. 31, 2011
|
Dec. 31, 2010
|
| Schedule of Available-for-sale Securities [Line Items] |
|
|
| Available-for-sale Securities, Gross Unrealized Gain (Loss) |
$ (1,000,000) |
$ 900,000 |
| Available-for-sale securities, amortized cost |
183,357,000 |
347,260,000 |
| Available-for-sale securities, gross unrealized gains |
84,000 |
1,164,000 |
| Available-for-sale securities, gross unrealized losses |
1,103,000 |
264,000 |
| Available-for-sale Securities, estimated fair value |
182,338,000 |
348,160,000 |
| Marketable securities, continuous unrealized loss position: |
|
|
| Marketable securities, in loss position for less than 12 months, estimated fair value |
115,035,000 |
95,388,000 |
| Marketable securities, in loss position for less than 12 months, gross unrealized losses |
1,103,000 |
264,000 |
| Marketable securities, in loss position for 12 months or greater, estimated fair value |
0 |
0 |
| Marketable securities, in loss position for 12 months or greater, gross unrealized losses |
0 |
0 |
| Marketable securities, in loss position, estimated fair value |
115,035,000 |
95,388,000 |
| Marketable securities, in loss position, gross unrealized losses |
1,103,000 |
264,000 |
|
Available For Sale Securities Debt Maturities Within One Year [Member]
|
|
|
| Schedule of Available-for-sale Securities [Line Items] |
|
|
| Available-for-sale securities, amortized cost |
66,146,000 |
167,499,000 |
| Available-for-sale securities, gross unrealized gains |
30,000 |
398,000 |
| Available-for-sale securities, gross unrealized losses |
30,000 |
8,000 |
| Available-for-sale Securities, estimated fair value |
66,146,000 |
167,889,000 |
|
Available For Sale Securities Debt Maturities Over One Year To Two Years [Member]
|
|
|
| Schedule of Available-for-sale Securities [Line Items] |
|
|
| Available-for-sale securities, amortized cost |
97,538,000 |
177,268,000 |
| Available-for-sale securities, gross unrealized gains |
54,000 |
759,000 |
| Available-for-sale securities, gross unrealized losses |
854,000 |
256,000 |
| Available-for-sale Securities, estimated fair value |
96,738,000 |
177,771,000 |
|
Available For Sale Securities Debt Maturities Over Two Years To Three Years [Member]
|
|
|
| Schedule of Available-for-sale Securities [Line Items] |
|
|
| Available-for-sale securities, amortized cost |
19,673,000 |
2,493,000 |
| Available-for-sale securities, gross unrealized gains |
0 |
7,000 |
| Available-for-sale securities, gross unrealized losses |
219,000 |
0 |
| Available-for-sale Securities, estimated fair value |
19,454,000 |
2,500,000 |
|
Commercial Paper, Not Included with Cash and Cash Equivalents [Member]
|
|
|
| Schedule of Available-for-sale Securities [Line Items] |
|
|
| Available-for-sale securities, amortized cost |
9,192,000 |
13,340,000 |
| Available-for-sale securities, gross unrealized gains |
1,000 |
3,000 |
| Available-for-sale securities, gross unrealized losses |
0 |
0 |
| Available-for-sale Securities, estimated fair value |
9,193,000 |
13,343,000 |
|
Corporate Debt Securities [Member]
|
|
|
| Schedule of Available-for-sale Securities [Line Items] |
|
|
| Available-for-sale securities, amortized cost |
55,150,000 |
98,148,000 |
| Available-for-sale securities, gross unrealized gains |
13,000 |
592,000 |
| Available-for-sale securities, gross unrealized losses |
152,000 |
138,000 |
| Available-for-sale Securities, estimated fair value |
55,011,000 |
98,602,000 |
| Marketable securities, continuous unrealized loss position: |
|
|
| Marketable securities, in loss position for less than 12 months, estimated fair value |
47,763,000 |
33,018,000 |
| Marketable securities, in loss position for less than 12 months, gross unrealized losses |
152,000 |
138,000 |
| Marketable securities, in loss position for 12 months or greater, estimated fair value |
0 |
0 |
| Marketable securities, in loss position for 12 months or greater, gross unrealized losses |
0 |
0 |
| Marketable securities, in loss position, estimated fair value |
47,763,000 |
33,018,000 |
| Marketable securities, in loss position, gross unrealized losses |
152,000 |
138,000 |
|
Federal Agency Debt [Member]
|
|
|
| Schedule of Available-for-sale Securities [Line Items] |
|
|
| Available-for-sale securities, amortized cost |
50,035,000 |
45,858,000 |
| Available-for-sale securities, gross unrealized gains |
54,000 |
21,000 |
| Available-for-sale securities, gross unrealized losses |
8,000 |
4,000 |
| Available-for-sale Securities, estimated fair value |
50,081,000 |
45,875,000 |
| Marketable securities, continuous unrealized loss position: |
|
|
| Marketable securities, in loss position for less than 12 months, estimated fair value |
6,744,000 |
11,721,000 |
| Marketable securities, in loss position for less than 12 months, gross unrealized losses |
8,000 |
4,000 |
| Marketable securities, in loss position for 12 months or greater, estimated fair value |
0 |
0 |
| Marketable securities, in loss position for 12 months or greater, gross unrealized losses |
0 |
0 |
| Marketable securities, in loss position, estimated fair value |
6,744,000 |
11,721,000 |
| Marketable securities, in loss position, gross unrealized losses |
8,000 |
4,000 |
|
Foreign Agency Debt [Member]
|
|
|
| Schedule of Available-for-sale Securities [Line Items] |
|
|
| Available-for-sale securities, amortized cost |
11,473,000 |
132,860,000 |
| Available-for-sale securities, gross unrealized gains |
0 |
425,000 |
| Available-for-sale securities, gross unrealized losses |
545,000 |
120,000 |
| Available-for-sale Securities, estimated fair value |
10,928,000 |
133,165,000 |
| Marketable securities, continuous unrealized loss position: |
|
|
| Marketable securities, in loss position for less than 12 months, estimated fair value |
8,176,000 |
46,134,000 |
| Marketable securities, in loss position for less than 12 months, gross unrealized losses |
545,000 |
120,000 |
| Marketable securities, in loss position for 12 months or greater, estimated fair value |
0 |
0 |
| Marketable securities, in loss position for 12 months or greater, gross unrealized losses |
0 |
0 |
| Marketable securities, in loss position, estimated fair value |
8,176,000 |
46,134,000 |
| Marketable securities, in loss position, gross unrealized losses |
545,000 |
120,000 |
|
Foreign Government Obligations [Member]
|
|
|
| Schedule of Available-for-sale Securities [Line Items] |
|
|
| Available-for-sale securities, amortized cost |
9,128,000 |
9,137,000 |
| Available-for-sale securities, gross unrealized gains |
1,000 |
8,000 |
| Available-for-sale securities, gross unrealized losses |
9,000 |
2,000 |
| Available-for-sale Securities, estimated fair value |
9,120,000 |
9,143,000 |
| Marketable securities, continuous unrealized loss position: |
|
|
| Marketable securities, in loss position for less than 12 months, estimated fair value |
6,361,000 |
4,515,000 |
| Marketable securities, in loss position for less than 12 months, gross unrealized losses |
9,000 |
2,000 |
| Marketable securities, in loss position for 12 months or greater, estimated fair value |
0 |
0 |
| Marketable securities, in loss position for 12 months or greater, gross unrealized losses |
0 |
0 |
| Marketable securities, in loss position, estimated fair value |
6,361,000 |
4,515,000 |
| Marketable securities, in loss position, gross unrealized losses |
9,000 |
2,000 |
|
Supranational Debt [Member]
|
|
|
| Schedule of Available-for-sale Securities [Line Items] |
|
|
| Available-for-sale securities, amortized cost |
46,380,000 |
47,917,000 |
| Available-for-sale securities, gross unrealized gains |
0 |
115,000 |
| Available-for-sale securities, gross unrealized losses |
389,000 |
0 |
| Available-for-sale Securities, estimated fair value |
45,991,000 |
48,032,000 |
| Marketable securities, continuous unrealized loss position: |
|
|
| Marketable securities, in loss position for less than 12 months, estimated fair value |
45,991,000 |
|
| Marketable securities, in loss position for less than 12 months, gross unrealized losses |
389,000 |
|
| Marketable securities, in loss position for 12 months or greater, estimated fair value |
0 |
|
| Marketable securities, in loss position for 12 months or greater, gross unrealized losses |
0 |
|
| Marketable securities, in loss position, estimated fair value |
45,991,000 |
|
| Marketable securities, in loss position, gross unrealized losses |
389,000 |
|
|
US Government Debt Securities [Member]
|
|
|
| Schedule of Available-for-sale Securities [Line Items] |
|
|
| Available-for-sale securities, amortized cost |
1,999,000 |
|
| Available-for-sale securities, gross unrealized gains |
15,000 |
|
| Available-for-sale securities, gross unrealized losses |
0 |
|
| Available-for-sale Securities, estimated fair value |
$ 2,014,000 |
|