FAIR VALUE MEASUREMENTS - Fair Value of Financial Assets and Liabilities Not Measured at Fair Value (Details) $ in Thousands	Dec. 31, 2017 USD ($)	[1]
Fair Value Disclosures [Abstract]
Carrying Amount	$ 25,438
Fair Value	$ 32,792

[1] (1)See Note 2, Adoption of New Accounting Standards, and Note 6, Investments, for information about our adoption of ASU 2016-01 on January 1, 2018 and its impact on accounting for equity investments without readily determinable fair values that were previously subject to the cost method of accounting.