|
FAIR VALUE MEASUREMENTS (Details) (USD $)
In Thousands, unless otherwise specified |
Dec. 31, 2011
|
Dec. 31, 2010
|
|---|---|---|
| Assets: | ||
| Marketable securities: | $ 165,695 | $ 563,997 |
|
Fair value on a recurring basis | Quoted Market Prices in Active Markets for Identical Assets (Level 1)
|
||
| Assets: | ||
| Total Assets | 400,672 | 490,321 |
|
Fair value on a recurring basis | Quoted Market Prices in Active Markets for Identical Assets (Level 1) | Treasury and government agency money market funds
|
||
| Assets: | ||
| Cash equivalents: | 321,314 | 275,108 |
|
Fair value on a recurring basis | Quoted Market Prices in Active Markets for Identical Assets (Level 1) | U.S. Treasury securities
|
||
| Assets: | ||
| Marketable securities: | 199,899 | |
|
Fair value on a recurring basis | Quoted Market Prices in Active Markets for Identical Assets (Level 1) | Marketable equity security
|
||
| Assets: | ||
| Marketable securities: | 4,667 | 15,314 |
|
Fair value on a recurring basis | Quoted Market Prices in Active Markets for Identical Assets (Level 1) | Long-term marketable equity securities
|
||
| Assets: | ||
| Long-term investments: | 74,691 | |
|
Fair value on a recurring basis | Significant Other Observable Inputs (Level 2)
|
||
| Assets: | ||
| Total Assets | 403,720 | 684,017 |
|
Fair value on a recurring basis | Significant Other Observable Inputs (Level 2) | Commercial paper
|
||
| Assets: | ||
| Cash equivalents: | 237,942 | 309,183 |
|
Fair value on a recurring basis | Significant Other Observable Inputs (Level 2) | Time deposits
|
||
| Assets: | ||
| Cash equivalents: | 4,750 | 26,050 |
|
Fair value on a recurring basis | Significant Other Observable Inputs (Level 2) | Corporate debt securities
|
||
| Assets: | ||
| Marketable securities: | 48,705 | 238,163 |
|
Fair value on a recurring basis | Significant Other Observable Inputs (Level 2) | States of the U.S. and state political subdivisions
|
||
| Assets: | ||
| Marketable securities: | 112,323 | 110,621 |
|
Fair value on a recurring basis | Significant Unobservable Inputs (Level 3)
|
||
| Assets: | ||
| Total Assets | 5,870 | 13,100 |
| Liabilities: | ||
| Contingent consideration arrangement | (10,000) | |
|
Fair value on a recurring basis | Significant Unobservable Inputs (Level 3) | Auction rate securities
|
||
| Assets: | ||
| Long-term investments: | 5,870 | 13,100 |
|
Fair value on a recurring basis | Total Fair Value Measurements
|
||
| Assets: | ||
| Total Assets | 810,262 | 1,187,438 |
| Liabilities: | ||
| Contingent consideration arrangement | (10,000) | |
|
Fair value on a recurring basis | Total Fair Value Measurements | Treasury and government agency money market funds
|
||
| Assets: | ||
| Cash equivalents: | 321,314 | 275,108 |
|
Fair value on a recurring basis | Total Fair Value Measurements | Commercial paper
|
||
| Assets: | ||
| Cash equivalents: | 237,942 | 309,183 |
|
Fair value on a recurring basis | Total Fair Value Measurements | Time deposits
|
||
| Assets: | ||
| Cash equivalents: | 4,750 | 26,050 |
|
Fair value on a recurring basis | Total Fair Value Measurements | Corporate debt securities
|
||
| Assets: | ||
| Marketable securities: | 48,705 | 238,163 |
|
Fair value on a recurring basis | Total Fair Value Measurements | States of the U.S. and state political subdivisions
|
||
| Assets: | ||
| Marketable securities: | 112,323 | 110,621 |
|
Fair value on a recurring basis | Total Fair Value Measurements | U.S. Treasury securities
|
||
| Assets: | ||
| Marketable securities: | 199,899 | |
|
Fair value on a recurring basis | Total Fair Value Measurements | Marketable equity security
|
||
| Assets: | ||
| Marketable securities: | 4,667 | 15,314 |
|
Fair value on a recurring basis | Total Fair Value Measurements | Auction rate securities
|
||
| Assets: | ||
| Long-term investments: | 5,870 | 13,100 |
|
Fair value on a recurring basis | Total Fair Value Measurements | Long-term marketable equity securities
|
||
| Assets: | ||
| Long-term investments: | $ 74,691 |