v3.6.0.2

FAIR VALUE MEASUREMENTS - Fair Value of Financial Assets and Liabilities (Details) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2016 | Dec. 31, 2015
Fair value measurements |  |
Investments in securities | $ 33,383 | $ 38,624
Total financial assets | $ 280,316 | 217,496
Convertible notes |  |
Fair value measurements |  |
Investments in securities |  | 635
U.S. treasury bills |  |
Fair value measurements |  |
Maximum investment term | 12 months |
Cash and cash equivalents | $ 44,999 | 100,996
Investments in securities | 32,995 | 37,989
Government securities money market |  |
Fair value measurements |  |
Cash and cash equivalents | 201,934 | 77,876
Common Stock |  |
Fair value measurements |  |
Investments in securities | 388 |
Level 1 |  |
Fair value measurements |  |
Total financial assets | 388 | 91,988
Level 1 | U.S. treasury bills |  |
Fair value measurements |  |
Cash and cash equivalents |  | 71,998
Investments in securities |  | 19,990
Level 1 | Common Stock |  |
Fair value measurements |  |
Investments in securities | 388 |
Level 2 |  |
Fair value measurements |  |
Total financial assets | 279,928 | 124,873
Level 2 | U.S. treasury bills |  |
Fair value measurements |  |
Cash and cash equivalents | 44,999 | 28,998
Investments in securities | 32,995 | 17,999
Level 2 | Government securities money market |  |
Fair value measurements |  |
Cash and cash equivalents | $ 201,934 | 77,876
Level 3 |  |
Fair value measurements |  |
Total financial assets |  | 635
Level 3 | Convertible notes |  |
Fair value measurements |  |
Investments in securities |  | $ 635

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