FAIR VALUE MEASUREMENTS - FAIR VALUE OF COMPANY'S FINANCIAL ASSETS AND LIABILITIES REMEASURED ON A RECURRING BASIS (Details) - Fair value measurements recurring basis - Money market funds - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Financial Assets:
Total financial assets	$ 80,990	$ 90,524
Level 1
Financial Assets:
Total financial assets	80,990	90,524
Level 2
Financial Assets:
Total financial assets	0	0
Level 3
Financial Assets:
Total financial assets	$ 0	$ 0