ORGANIZATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Recently Adopted and Issued Accounting Pronouncements (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
	Jan. 01, 2020	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2020
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Accounting Standards Update [Extensible List]				us-gaap:AccountingStandardsUpdate201613Member
Investment, long-term loan receivable	$ 3,500
Credit loss on finance receivable				$ 1,900
Convertible debt
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reacquisition of equity component		$ 2,718	$ 16,814
Convertible Senior Notes, 5.0% | Convertible debt
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reacquisition of equity component	$ 19,500	$ 2,700	$ 16,800